ٍSubject Review: The Status of Horticulture Protection and Using Pesticides in Gaza Strip

ٍSubject Review: The Status of Horticulture Protection and Using Pesticides in Gaza Strip

Ahmad S. Saleh, Ismael Abdel Aziz

Received : 28-12-1998 , Accepted : 17-12-2002

Language: Arabic

Abstract

A field study has been conducted in Gaza governorates to evaluate status of plant protection and using pesticides by farmers. To achieve this goal a questionnaire of 31 questions has been prepared and answered by a randomly chosen sample of 48 farmers representing the agricultural density of each governorate. It covered the northern area, Gaza, middle region, Khanyunis and Rafah governorate. The study shows that most farmers who have been included in this questionnaire are characterized as having an educational level beyond the preparatory stage; they are either young or older more than 51 years. They also have crucial relationship with their farms. These farmers have not been given sufficient training on new techniques of plant protection and on the safe use of pesticides. In addition the study shows that many dangerous pests and weeds have attacked the fruit trees and also the agricultural extension agents play an essential role in extension and in direction of the farmer towards selecting the pesticides which will be used on crops, and most of farmers depends on chemical method in their attempt to control the plant diseases and pests, however few of them depend on alternative techniques. Although, they prefer other alternatives which are safer to the environment, the variations among farmers in terms of the quantity (dosage) used of pesticide. The study showed that farmers used high volume technique in spraying the pesticide, the farmers may spray the pests during three times a day (morning or noon or evening). They either use motorized Knapsack sprayer or tractor sprayer or, lever operated knapsack sprayer or manual sprayer motor. The farmers reuse the remaining spray solution to spray their crops without taking into consideration the quantity needed for each crop area. Although farmers get their pesticides from local market, they believe that such pesticides are dangerous, expensive, and ineffective. Furthermore, the study shows that some crops like, grapes, apples are considered among the most frequently sprayed crops with pesticides. It also shows that diseases, which affect these crops, constitute major economic losses for the farmers more than losses caused by insect and mites. The contrary previous crops caused in guava, almonds, olives, citrus, by insects and mites constitute a major economic caused for the farmers more than losses caused by plant diseases. The study showed also list of pesticides, which are used to control for each pests and diseases of different fruit trees.

Full Text

Composition Operators on Orlicz and Bochner Spaces

Composition Operators on Orlicz and Bochner Spaces

Mahmud Masri

Mathematics Department, Faculty of Science, An-Najah National University, Nablus, Palestine.

Received : 16-09-2000 , Accepted : 07-05-2001

Language: English

Abstract

Full Text

Electophysiological assessments of the effects of Glycemic events, Ascorbic acid and Thaimine, on the Peripheral Neuropathy of Diabetes Mellitus Patie

Electophysiological assessments of the effects of Glycemic events, Ascorbic acid and Thaimine, on the Peripheral Neuropathy of Diabetes Mellitus Patients

I.W.M. Al- Hasan*, G.A. Al- Sharify**

*Faculty of Pharmacy, An-Najah National University, Nablus, Palestine. **Al-Yarmouk Hospital, Baghdad

Received : 06-02-2001 , Accepted : 05-11-2001

Language: English

Abstract

Three groups of patients who had diabetes mellitus for 10 years were enrolled in the study and compared with the control group. Electrophysiological study on seven peripheral nerves were carried out once in the control subjects and four times in the diabetic patients; the first examination was conducted prior to drug supplement and the subsequent reexaminations conducted at the end of 6; 12 and 18 months following the drugs treatments, ascorbic acid (AA) and Thiamine (B1). The results indicate that improvements in latency, velocity and amplitude of the nerves evoked responses were significantly better with the use of AA compared to thiamine use in the patients. The results also show that the improvements were significantly greater in insulin dependent diabetes mellitus (IDDM) compared to that of non insulin dependent diabetes mellitus (NIDDM) patients with the presence of AA in both groups.Nevertheless the results indicate that with better glycemic control, the tested nerves show variable degrees of functional improvements detected by the three examined parameters at the end of the 6 and 12 months. At the end of the last visit (18 months after the first visit) more improvements were observed in the three parameters of IDDM patients. Key words: Ascorbic acid, Thiamine, Insulin, effectiveness, Diabetic Neuropathy.

Full Text

Adsorptive Cathodic Stripping Voltammetric Studies of Emodin

Adsorptive Cathodic Stripping Voltammetric Studies of Emodin

Mohammad A. Hannoun

Faculty of Pharmacy, An- Najah National University- Nablus, West Bank (Palestine)

Received : 22-09-1998 , Accepted : 31-08-1999

Language: English

Abstract

A differential pulse cathodic stripping voltammetric (DP-CSV) method for determination of emodin in Britton- Robinson buffer (pH2) at a hanging mercury drop electrode (HMIDE) is described. The method is based on measuring the reductive peak height at —0.25V vs. Ag/AgCl reference electrode. The linear relationship between the peak current and emodin concentration allowed the voltarnmetric determination of emodin over a wide concentration range 1.0 X 10-2 —2.5 X10-6 M, with a relative standard deviation of 3.3% (10 determinations at 1 X 10-2 M). Adsorption of emodin at HMDE enabled a detection limit of 2X10-1°M after 3 min accumulation at 0.0V. The applicability of the suggested method was found to be suitable for the determination of emodin in roots, stems and leaves of Rumex cyprius plant.

Full Text

Run-Time Elimination of Dead-Rules in Forward-Chaining Rule-Based Programs

Run-Time Elimination of Dead-Rules in Forward-Chaining Rule-Based Programs

Wael Mustafa

Computer Science Department, An-Najah N. Univ., Nablus, Palestine.

Received : 29-08-1998 , Accepted : 04-07-1999

Language: English

Abstract

This paper presents an optimization method to improve execution time of forward-chaining rule based programs. The improvement is achieved by deleting rules that finish firing during run-time. The conditions of the deleted rules are not matched against working memory in later execution cycles and hence the execution time is reduced. Information obtained from control and data-flow analyses is utilized to determine when rules finish firing during nm-time. Since rules are deleted during run-time only after they finish firing the optimization does not change the semantics of the source program. The optimization method can be n final step to other optimization methods. The results of applying the optimization to three CLIPS rule-based programs are presented. These results show significant improvement when the source program contains rules that require significant matching time and finish execution early during run-time.

Full Text

Extended X-ray Absorption Fine Structure Study on Ge28.33 In6 Se65.67 Glass

Extended X-ray Absorption Fine Structure Study on Ge28.33 In6 Se65.67 Glass

Ghassan Saffarini

Physics Department, Faculty of Science, An-Najah National University, Nablus, Palestine.

Received : 06-10-1997 , Accepted : 24-05-1999

Language: English

Abstract

The local environment of indium atoms in the chalcogenide glass with the stoichiometric composition Ge28. 33 In6 Se65 67 has been investigated using extended X-ray absorption fine structure (EXAFS) technique. It is found that indium is only coordinated with selenium atoms with a value of three for its coordination number.

Full Text

Performance of Different Grape Cultivars for Rooting and Grafting

Performance of Different Grape Cultivars for Rooting and Grafting

Hassan Abu-Qaoud

Dept. of Plant Prod. & Prot., Faculty of Agriculture, An-Najah Nat. Univ. Nablus, Palestine.

Received : 10-06-1998 , Accepted : 21-02-1999

Language: English

Abstract

Four local grape cultivars (Halawani, Beiruiti Zaini and Beituni) were bench grafted on four different grape rootstocks (B41, Paulsen, Rugerri and Richter). Two grafting methods were used: whip tongue and wedge grafting. The experiment was conducted for two successive seasons (1997 and 1998). All rootstock basis were treated with Indolebutyric- acid (IBA) at 8000 ppm in the form of powder. The results showed a great variability in the rooting ability of the different rootstocks with Paulsen rootstock which resulted in the higher rooting ability, while Rugerri and B41 resulted significantly in the lower rooting percentage in both seasons. The scion as well as the grafting method did not affect the rooting ability of the rootstocks. The rootstock scion combination showed high healing ability with a significant interaction between both graft partners. Rugerri and Richter resulted in the highest healing of grafts. The vegetative bud growth of the graft varied among the different scion cultivars but without any significant effect of grafting method or rootstocks in both seasons. Both Halawani and Beiruiti resulted in the higher vegetative growth during propagation.

Full Text

Effects of Urea Feeding on Milk Characteristics of Baladi Goats

Effects of Urea Feeding on Milk Characteristics of Baladi Goats

Jamal Abo Omar, Hassan Abu Qaoud, Hatim Shanti

Faculty of Agriculture, An-Najah N. University-Nablus, Palestine.

Received : 00-00-0000 , Accepted : 00-00-0000

Language: Arabic

Abstract

Two feeding trials were conducted on local goats to investigate the effect of urea on both quantity and quality of milk. In the first trial, two groups of lactating goats were fed similar commercial feed plus 1% urea in the feed of one group. In the second trial, same number of pregnant goats were used to investigate urea feeding on colostrum and milk quality. Urea addition in experiment 1 had no significant effect on total milk production, total milk protein, casein, but significantly (P<.05) increased total solids and milk fat. In the second experiment, urea had similar effects as in the first experiment. Colostrum composition was not affected by urea treatment.

Full Text

Construction of MIM Diodes Suitable for Use in FIR Generation By Mixing Two Carbon Dioxide Laser Beams

Construction of MIM Diodes Suitable for Use in FIR Generation By Mixing Two Carbon Dioxide Laser Beams

Mohammad Abu-Taha

Physics Department, College of Science and Technology, Al-Quds Univ., Jerusalem, Palestine

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

Metal Insulator Metal (MIM) diodes have been constructed with a tungsten whisker making contact with different post materials such as nickle, brass, carbon, stainless steel, aluminum and tungsten. The 1-V characteristics of these diodes have been studied. It was found that 2 mm section cut from a shaving blade held against a polished carbon post showed similar I-V characteristics to the previous diodes. Resistances of these diodes were found to vary between 0.1-1k The use of MIM diodes for CO2 laser mixing is briefly discussed.

Full Text

Comparative Analysis of Techniques for Solving the Hydraulics of Pressurized Irrigation Pipe Networks

Comparative Analysis of Techniques for Solving the Hydraulics of Pressurized Irrigation Pipe Networks

Numan Mizyed

Plant Production Department, Faculty of Agriculture, An-Najah N. Univ., Nablus, Palestine.

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

This study presents a comparative analysis for three techniques in analyzing the hydraulics of pressurized irrigation systems: Linear Theory, Newton Raphson, and Iterative Distal Outlet. It was found that the iterative distal outlet method uses less computer time and memory than Newton Raphson and Linear theory methods in analyzing the hydraulics of pressurized irrigation systems. The study shows that using an approximate initial solution for such systems, which can be obtained using Wu-Gitlin approach, will significantly improve the convergence rate of this iterative method as well as the other methods.

Full Text

The Effect of Monensin, Lasalocid and a Monensin/Lasalocid Rotation of Fungal Population in the Rumen of Concentrate and Roughage Fed Steers

The Effect of Monensin, Lasalocid and a Monensin/Lasalocid Rotation of Fungal Population in the Rumen of Concentrate and Roughage Fed Steers

Jamal Abo-Omar

Assistant Professor, Dept of Animal Production, An-Najah N. University, Nablus

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

Two studies using three ruminally cannulated beef steers in the first one fed a roughage diet (98% chopped alfalfa at maintenance) and 12 beef steers in the second fed limited ration (85% adlib intake) composed of 90% concentrate diet (80% cracked corn, 10% soybean meal), and 10% chopped alfalfa were allotted to treatment groups receiving a supplement of either monensin / tylan (m27.5 ppm / 11 ppm), lasalocid (33 ppm) or a daily rotation of the two ionophores to examine the effect of the ionophores on rumen population of anaerobic fungi over time and the relationship between fungal numbers and methane production. In the first study, nylon bags containing leaf blades of 5mm length were incubated for 24 hrs in the rumen. Samples were counted on days 0, 1, 3, 5, 7, 11, 14, 16, 21, 22, 23, 24, and 28 Fungi sporangia on blades were counted microscopically (00x). Study 2, steers were assigned as above and after methane production was measured using indirect respiration calorimetry, samples of rumen contents were collected by stomach tube pretreatment, and on days 2, S, 16, and 45 after initiation of ionophore treatments. Differences of fungi numbers over time and between treatments were not significant, yet, there was a trend of initial ionophore inhibition on fungi with limited evidence of adaptation over time there was a positive correlation (P <>

Full Text

Indoor Radon Concentration Measurements At Hebron University Campus :A Case Study

Indoor Radon Concentration Measurements At Hebron University Campus :A Case Study

Fakhri I. Hasan

Associate Professor, Physics Department, Hebron University, Hebron

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

TASTRAK, a solid state nuclear track detector has been used to measure indoor radon concentrations at Hebron University. Fifty- four radon pot detectors were mounted in the four university buildings. It was found that the radon concentrations vary considerably from about 1 Bq/m 3 to 250 Bq/m3 The average radon concentrations vary from 20.5 Bq/m3 in the Main Building to 41.3 Bq/m3 in the Agriculture Building. The average radon concentration in the four buildings is found to be 29.8 Bq/m 3. This leads to an average effective dose equivalent of 1.49 mSvly. This dose is slightly higher than the global value of 1.3 mSv/y. Elevated radon concentrations have been found in few rooms. However, these concentrations are well below the action level of 150 Bq/m3.

Full Text

Evaluation of the Stiffness Matrix of an Indeterminate Truss Using Minimization Techniques

Evaluation of the Stiffness Matrix of an Indeterminate Truss Using Minimization Techniques

Samir H. Helou

Assistant Professor, Civil Engineering, An-Najah National University, Nablus.

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

For an existing reinforced concrete or steel structure the evaluation of the stiffness matrix may be hampered by certain physical limitations such as material deterioration resulting from prolonged use an adverse or in a corrosive environment. The following is a method that allows the determination of the member stiffness of an indeterminate truss through a minimization technique of a properly constructed Error Function. Thus exact sectional and material properties do not have to be known a priori.

Full Text

Cluster Catalysis of Olefin Hydrosilylation and Isomerization Thermal Reaction Using Co4(Co)10(PPh)2

Cluster Catalysis of Olefin Hydrosilylation and Isomerization Thermal Reaction Using Co4(Co)10(PPh)2

Waheed J. Jondi

Assistant Professor Dept. of Chem., An-Najah N. University, Nablus.

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The cobalt cluster [Co4(C0)10(PPh)2], 1/~, has been evaluated as a catalyst for 1-octene thermal hydrosilylation and isomerization reactions. The kinetics indicates that the hydrosilylation reaction occurs via cluster catalysis at temperatures ranging from 50-70°c. The 1 - octene isomerization was selective to trans-2-octene only. The kinetics indicates that at 50°c or lower isomerization reaction occurs via cluster catalysis whereas at 70°c or higher catalysis by lower nuclearity species is involved. The effects of solvent silane temperature and catalyst and reactant concentrations on the rates of hydrosilylation and isomerization reactions have been investigated. Plausible mechanisms based on experimental data have been proposed.

Full Text

The Effects of Substrate Material, Quenching and Annealing on the Properties of High Temperature Superconductor BSCCO (Bi-2212) Thick Tapes

The Effects of Substrate Material, Quenching and Annealing on the Properties of High Temperature Superconductor BSCCO (Bi-2212) Thick Tapes

Abed Al-Kariem Saleh, Dived Haase

1 Associate professor, Al-Quds University, College of Science & Technology, Jerusalem, Abu Deis; 2 Physics Dept., North Carolina State Univ., Raleigh, NC, USA.

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The effects of substrate material and heat treatment conditions on the electrical and thermal properties for partially melt-solidified superconducting tapes BSCOO (2212), grown on single crystal MgO and Ag MgO substrates m were investigated. Results show that the resistivity of the normal state varies with the size and orientation of the grains. It is found that larger grains lower both the concentration of second phases and the grain boundaries, hence decreasing the resistivity of the normal state and enhancing the critical current density of the superconducting state. Also, the material of the substrate has no effect on either the resistivity or the critical current density of the Bi-2212 phase. Heat treatment conditions and the annealing atmosphere play an important role in determining the critical current density and the transition temperature. Slow cooling from 840°C lowers both the critical current and the transition temperature; while quenching the sample from 840°C to room temperature and annealing it in a nitrogen atmosphere increase both the critical current density and the transition temperature.

Full Text

On Composition Operators on A2

On Composition Operators on A2

Mahmud Ilayyan Masri

Department of Mathematics, An-Najah National University

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

If (?) is an analytic function mapping the open unit disk D into itself and A2 is the Bergman space of analytic functions on D, the compositon operator C?, on A2 is defined by C?f=fo?feA2. In this paper we consider the spectral radius, unitary equivalence, sub-normality of C? and study the case ?(z) = zm, m = 2, 3,….. in detail.

Full Text

Microbiological Screening of the Environments of Two Hospitals in Nablus

Microbiological Screening of the Environments of Two Hospitals in Nablus

Yahya Faydi, Abdel Hadi Hamdan, Mohammed Saleem Ali Shtayeh, Suleiman Al-Khalil

1 Department of Medical Laboratory Sciences; 2 Department of Biological Sciences, An-Najah University

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

Both blood agar and MacConkey plates were used for the isolation of bacteria from the environments of two hospitals in Nablus. Pseudomonas aeruginosa, Escherichia coli and Staphylococci were isolated from saline solution kept in glass bottles for washing and cleansing wounds, suction machines, respirators, endotracheal tubings, oxygen pumps and sinks. Alcaligenes odorans was isolated from the suction machines and Dettol solution. Aeromonas species were isolated from deionized water and sinks, the implications of these findings were also discussed.

Full Text

The Effect of Different Seed Treatments on Seed Germination of Gundelia tournefortii Seeds

The Effect of Different Seed Treatments on Seed Germination of Gundelia tournefortii Seeds

Hassan Abu-Qaoud, Rae'd Alkoni

1 Department of plant Production and Protection, Faculty of Agriculture, An- Najah N. University; 2 Palestinian Agriculture Relief Committees

Received : 00-00-0000 , Accepted : 00-00-0000

Language: Arabic

Abstract

The effects of different seed treatments on the germination percentage and rate of Gundelia tournefortii seeds were studied. Seeds were collected from Jamaeen area near Nablus city. The normal healthy seeds were separated from small shrinked seed and used in the different trails. Three experiments were conducted in which the effect of presoaking, scarification and stratification on the seed germination was investigated. The higher germination percentage (48%) was obtained when the outer seed coat was removed after the seeds were presoaked in water. This percentage was highly significant than other results obtained with the other treatments. The use of concentrated sulfuric acid for 15 and 30 minutes to tender the seed coat didn't increase the germination percentage of the treated seeds over that of the control Similar effects was also exhibited when the seeds were soaked in hot water for different intervals. Cold stratification at 4-5' didn't significantly increase the germination percentage of the seeds.

Full Text

Decay of the Charged Harmonic Oscillator

Decay of the Charged Harmonic Oscillator

Sami M. Al-Jaber, Walter C. Henneberger

1 Department of Physics, An-Najah National University; 2 Department of Physics and Southern Illinois University Molecular Science Program, Southern Illinois University, Carbondale, Illinois U.S.A.

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

We apply the van Kampen-Steinwedel principal axis transformation to the problem of finding time-dependent probability distributions for decaying states of the harmonic oscillator. The result lends itself easily to computer simulation. Results for the decay of levels 1,2, and 15 are given.

Full Text

The Electronic Structure of Gax In 1-x As and InASx P1-x Using the Recursion Method

The Electronic Structure of Gax In 1-x As and InASx P1-x Using the Recursion Method

Mousa Al- Hasan

Department of Physics, An-Najah N. University, presented at the second conference on Physics of condensed Matter, Amman, 20-24 March, 1989 and updated 1993.

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The calculation of the electronic structure of Gax In 1-x As and In Asx P1-x alloys using the recursion method is reported. A five-orbitals, sp3s*, per atom model is used in the tight-binding representation of the Hamiltonian. The local density of states is calculated for Ca, In, As and P-sites in a cluster of 216 atoms. The results are in good agreement with other calculations.

Full Text

Visceral Organ Mass of Lambs Fed Four Roughage Diets

Visceral Organ Mass of Lambs Fed Four Roughage Diets

J. M. Abo Omar, K. Johnson, D. Johnson

1 Department of Animal Production, Faculty of Agriculture, An-Najah N. University, Nablus, West-Bank; 2 -3 Present Address: Colorado State University, Fort Conks, Co 30523

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

Twenty-eight lambs averaging 45 kg live weight were divided among four roughage dietary treatment : grass hay, corn silage, alfalfa and oat hay. The diets contained a minimum of 12% crude protein and provided 10% over the required energy for maintenance. Lambs were fed twice a day (0800 and 1700) for 28 days. Animals were weighed at 10-d intervals at 0700 prior to being fed that morning. At the end of the feeding period the lambs were slaughtered and the weights of fat-free gastrointestinal tract segments, their content and other organs were taken and expressed as g/kg of empty body weight (EBW) Sampled of the rumen and small intestine were separated into mucosa] and nonmucosal (serosal) fractions. No single forage diet consistently increased the weights of all visceral organs. However, lambs fed the 70% alfalfa hay has 12% heavier liver and lung weights (p < .05) compared to lambs receiving other treatments and 11% heavier small intestine weights compared to the oat and silage diets. The grass hay diets resulted in lambs with 55% heavier cecum dry weights (P < . 05) compared to other roughage sources . Lambs fed silage diets had 7% heavier rumen mucosa (wet and dry) weights . The roughage source had no effect on total rumen, omasum, large intestine and total tract weights or contents.

Full Text

Triangular Fuzzy Metric

Triangular Fuzzy Metric

Mohammad A. Mahmoud Al-Amleh

1 Mathematics Department, An-Najah N. University, Nablus-West Bank

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

This paper presents a new method to rank triangular fuzzy numbers as well as a new metric (triangular fuzzy metric) on the set of fuzzy points. This metric can be used in both studying fuzzy topological spaces and decision-making theory.

Full Text

Polymerization of 4-Methylpentene -1- by the MgCl2|Eb|TiCl4|Al(iBu)3 Catalyst System 1. Kinetic Investigations

Polymerization of 4-Methylpentene -1- by the MgCl2|Eb|TiCl4|Al(iBu)3 Catalyst System 1. Kinetic Investigations

M. A. Abu-Eid, P. J. Tait

1 Chemistry Department, An-Najah N. University, Nablus-Want Bank; 2 UMIST, Chemistry Department, Sackville Street Manchester, U.K.

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The kinetics of the polymerization of 4-methylpentcne-1- with the MgC12|EB|Ticl4|Al(iBu)3 catalyst systems have been investigated. The conditions and requirements to achieve the highest activity and stereospecificity of the MgC12-supported catalyst systems were discussed. Moreover, the role of aluminum alkyl and ethyl benzoate on the activity and stereo-regularity of the polymers have been reported.

Full Text

Polarographic Study of Some Arylidene-2-Pyridylhydrazones

Polarographic Study of Some Arylidene-2-Pyridylhydrazones

Ali Z. Abu-Zuhri, Mohammed A. Al-Nuri, Mohammed A. Hannoun, and Jamal S. Shalabi

Present address: Department of Chemistry, Faculty of Science, United Arab Emirates University, Al-Ain, UAE; This work is taken from the M. Sc. Thesis of Jamal S. Shalabi Department of Chemistry, Faculty of Science, An-Najah National University - Nablus.

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The polarographic behaviors of some arylidene-2-pyridyl hydrazones have been studied in aqueous Britton - Robinson buffer solution containing 40% ethanol using DC polarographic technique. In the pH range 1.9 - 6.4 the observed single irreversible 4 - electron reduction wave is attributed to the splitting of the N - N bond and saturation of C = N centre. All compounds studied are polarographically inactive in alkaline medium. The effect of pH on the limiting current and E 112 as well as the reduction mechanism and the effect of substituent's are discussed and compared with similar compounds. The kinetic parameters of the electrode reaction have been calculated.

Full Text

On Semilocal Rings And Finitely Generated Projective Modules

On Semilocal Rings And Finitely Generated Projective Modules

Ali Abdel-Mohsin

Mathematics Department, Faculty of Science, An-Najah National University-Nablus

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

We establish the equivalence between the existence of a cyclic projective right C-module P such that P/J (BP) is semisimple and BP is finitely generated (B = End (Pc)) and the existence of an idempotent element e in c such that trace (Pc) is finitely generated (and equals CeC) and C/S is semisimple where S is the intersection of all maximal left ideals of C not containing the trace ideal of Pc.

Full Text

Polymerization of Ethylene by the Silaned SiO2 -Mg(iBu)2-TiCl4-Al(iBu)3 Catalyst System

Polymerization of Ethylene by the Silaned SiO2 -Mg(iBu)2-TiCl4-Al(iBu)3 Catalyst System

M.A. Abu-Eid, P.J. Tait

1 Department of Chemistry, An-Najah National University-Nablus, West Bank; 2 Department of Chemistry, UMIST, Sackville Street, Manchester M60 1QD, UK

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The polymerization of ethylene was conducted over the Silaned Si02 / Mg(iBu)2 I TiCl I Al (mu)3 and over the Stauffer AA type (1.1)/Al (iBu)3 catalyst systems at 60° C. The activity of the Sb2 — supported catalyst was about one hundred times higher than that of Stauffer AA. The rate — time profiles for both catalysts were found to be of acceleration type • The dependence of the spontaneous rate of polymerization with [Al (mu)3 I has been established for the Si02 — supported catalyst. A maximum rate was achieved at Al: Ti ratio of 512:1. The rate of ethylene production using Si02 — supported catalyst was increased by a factor of two when the prepolymerization time with propylene was 10 minutes.

Full Text

Short Communication: Addition of Bis (methylthio) acetylene to Nitrilium Salts

Short Communication: Addition of Bis (methylthio) acetylene to Nitrilium Salts

Rajab Abu El-Halawa, J.C. Jochims

1 Assistant Prof. Department of Chemistry, Faculty of Science, An-Najah National University; 2 Prof. Dr. Department of Chemistry, Konstanz University, West Germany

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

Azaallenium salt 7 was isolated at low temperature by the addition of bis (methylthio) acetylene to nitrilium salts. The isolated azaallenium salt 7 was rearranged to afford the 1:1 heterocyclic adduct 8. A detailed mechanism is discussed.

Full Text

Mathematical Analysis of a Vibrating Rigid Water Tank

Mathematical Analysis of a Vibrating Rigid Water Tank

Amin H. Helou

Assistant Prof, Department of Civil Engineering, Faculty of Engineering, An-Najah National University.

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The hydrodynamic pressure distribution on the wall of a vibrating water tank is traditionally expressed as a summation of two components; an impulsive component and a convective one obtained by separating the potential function into two parts. This requires solving Laplace's equation in two stages each with a separate set of boundary conditions. The following is one step systematic solution to the problem in a frame moving with the tank. It proves to be simple, compact and could lead to the impulsive, frequency independent and the convective, frequency dependent components of pressure at the water tank wall.

Full Text

Free Odd Periodic Actions on the Solid Klein Bottle

Free Odd Periodic Actions on the Solid Klein Bottle

Fawas M. Abudiak

Assistant Prof., Department of Mathematics, Faculty of Science, An-Najah National University

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The cyclic actions of odd period and empty fixed point set are studied on the solid Klein Bottle K. It is shown that up to weak equivalence there is only one such action.

Full Text

Pollution Levels of Drinking Water in Several Villages in Nablus Area and in the City of Hebron

Pollution Levels of Drinking Water in Several Villages in Nablus Area and in the City of Hebron

R. Salim, I. Khatib, H. Hilal, Z. Qattawi, R. Abu-El-Halawa

An-Najah University, Nablus

Received : 00-00-0000 , Accepted : 00-00-0000

Language: Arabic

Abstract

Samples of drinking water were collected from several villages in Nablus area, and from the city of Hebron. The concentrations of lead, copper, nickel, manganese, iron, zinc, magnesium and calcium were determined in these samples using flame atomic absorption Spectroscopy. The obtained results were compared with the maximum allowed limit of concentration for each of these elements in drinking water.

Full Text

The Role of Solvent on the Kinetics and Mechanism of the Hydrolysis of Salicylidene Benzoyl Hydrazone

The Role of Solvent on the Kinetics and Mechanism of the Hydrolysis of Salicylidene Benzoyl Hydrazone

Maher Abu-Eid

Chemistry Department, An-Najah National University, Nablus

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The effect of various solvents on the kinetics and mechanism of the hydrolysis of Salicylidene Benzoyl hydrazone (SBH) has been studied at five different temperatures (17-45 C) using U.V. and visible spectrophotometry. In both protic and aprotic solvents, the hydrolysis rates follow first order kinetics. The role of solvent on the reaction rate, thermodynamic parameters and mechanism have been reported and discussed.

Full Text

A Detailed and Simplified Solution to Hydrodynamic Forces on a Submerged Tank Subject to Lateral Ground Excitation

A Detailed and Simplified Solution to Hydrodynamic Forces on a Submerged Tank Subject to Lateral Ground Excitation

A. H. Helou

Civil Engineering Department, An-Najah University, Nablus

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The domain where a submerged vertical cylindrical tank exists is divided into two regions. Assuming irrational motion and an ideal fluid the Laplace s equations in both regions are solved by the method of separation of variables. The integral equation resulting from matching the potentials at the interface is solved numerically by the Galerkin method. It is shown that the mathematical labor is greatly reduced by dropping the surface effects and the results are in good agreement with those obtained by including surface effects albeit at higher values of excitation frequencies. The case of protruding cylinder is presented to further illustrate the simplicity of the solution.

Full Text

Pollution Levels of Drinking Water in Nablus

Pollution Levels of Drinking Water in Nablus

H.S. Hilal, R. Salim and Z. Qattawi

An-Najah University, Nablus, West Bank

Received : 00-00-0000 , Accepted : 00-00-0000

Language: Arabic

Abstract

Metal concentrations in drinking water used in Nablus have been studied. Samples from houses located in various districts of Nablus have been collected between Dec. 22, 1985, and Jan. 19, 1986, acidified and then analyzed for their metal content of the elements lead, copper, zinc, nickel, iron, manganese, calcium and magnesium using flame atomic absorption spectroscopy with an acetylene-air flame The results showed that the concentrations of lead, copper, nickel, iron and manganese were well below the safe limits. The concentrations of both zinc and magnesium were high but still below the maximum limit allowed in drinking water. The concentration of calcium was found always above the allowed limit. The effect of storing water in tanks (this is very common in Nablus) on the concentration of the above elements has been studied. The only effect found for storing water in tanks was a decrease in the concentration of zinc from water. No effect was found for using sun-heaters on the concentrations of the above elements in water.

Full Text

Spectrophotometric Studies and Analytical Application of Cerium

Spectrophotometric Studies and Analytical Application of Cerium (III) and Thorium (IV) Chelates with Pyridine-2-Aldehyde-2-Pyridylhydrazone (PAPH)

Ali Z. Abu Zuhri; Mohammad A. Hannoun

Chemistry Department, An-Najah National University, Nablus, West Bank

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

Ce (III) and Th (IV) reacts with pyridine-2—aldehyde-2—pyridylhydrazone in aqueous solutions containing 50 % ethanol at pH's 7.75 and 8.45 respectively. Beer's law is obeyed over the range 0.0-15.p.g and 0.0-18 ktg of cerium and thorium respectively. The proposed procedure is sensitive, since molar absorptivity is 2.56 x 10 4 and 3.60 X 10 4 1.mol -1 cm-1 for Ce (III) and Th (IV) respectively. The composition and stability of these complexes have been determined. The limitation of this procedure and the effect of other ions have been studied.

Full Text

Pyridylazo Compounds As Analytical Reagents: A Review

Pyridylazo Compounds As Analytical Reagents: A Review

Ali Z. Abu-Zuhri

Chemistry Department, Faculty of Science, An-Najah National University, Nablus, West Bank

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

A large number of 2-pyridylazo compounds have been proposed as reagents for the spectrophotometric determination of several metal ions. The application of 2-pyridylazo compounds for the determination of many metal ions is listed and several procedures are described to illustrate the fundamental conditions for the spectrophotometric determination of these metal ions.

Full Text

Kinetic Study of the Complexation of Palladium (II) with 2-(5-Bromo-2-Pyridylazo)-5-Diethylaminophenol

Kinetic Study of the Complexation of Palladium (II) with 2-(5-Bromo-2-Pyridylazo)-5-Diethylaminophenol

Bassem F. Shraydeh; Ali Z. Abu Zuhri

Chemistry Department, Faculty of Science, An-Najah National University, Nablus, West Bank

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The kinetics of the complexation reaction of palladium with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) has been studied in the stability time at the optimum pH of 3.53 in presence of 50% ethanol. The effect of ionic strength and temperature on the reaction rate were reported. A mechanism has been postulated and the stability constants of the individual steps were determined. The Arrhenius and thermodynamic parameters were evaluated and discussed.

Full Text

The Development of Rotylenchulus Reniformis and Tylenchulus Semipenetrans, on Grape Roots

The Development of Rotylenchulus Reniformis and Tylenchulus Semipenetrans, on Grape Roots

S.A. Sultan

Agricultural Department, An-Najah National University, Nablus

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The results showed that the average numbers of eggs per an egg mass of R. Reniformis and T. Semipenetrans were 84 and 36 eggs, and the eggs hatched after 6 and 7 days respectively. The durations of the life cycle were 30 and 41 days, respectively. Life cycles were divided into migratory and sedentary phases. The migratory phase (soil phase) of R. reniformis was not parasitic and lasted for about 21 days; while that of T. semipenetrans was parasitic and lasted for about 31 days. The sedentary phase of both nematodes was parasitic and lasted for about 9 and 10 days for R. reniformis and T. semipenetrans respectively. Only the young females of R. reniformis were the infective stages; while all larval stages and young females of T. semipenetrans were able to penetrate root tissues.

Full Text

M.R.H. A New Era in Magnetic Head Design

M.R.H. A New Era in Magnetic Head Design

Mazen R. Husni

Faculty of Engineering, An-Najah University

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The conventional method for reading/writing information from/on a magnetic media (e.g. magnetic tapes in audio and video recorders, computers etc.) uses what is called an inductive head. This consists of several turns of enemelled wire, wound on a specially prepared former as shown in Fig.1. To write (record) information on the magnetic tape, a modulated current signal is injected into the coil. The current treats (induces) a magnetic field at the free ends of the former (poles) which in turn aligns the magnetic particles deposited on the tape, subsequently producing a record of the injected signal. To retrieve the information (i.e. playback the recorded signals) the prerecorded tape is swiped across the poles of the inductive head. In this case the reverse of the write cycle occurs i.e. the magnetic field from the tape influence the former in such a manner as to cause a current flow through the coil having the same form as the recorded signal. A major disadvantage of this type of head is its speed dependence. Since the head senses the rate of change of field, d?/dt (and not the field itself ? its output becomes greatly dependant' on the speed of the tape. Therefore, in tape system, and using an inductive head, it becomes necessary to use some form of electronic equalization in order to correct errors in the signal, resulting from any variations in the speed of the tape. In addition, because of their bulkiness, they become difficult to implement in applications where high packing densities (video tapes) or multi-track system (computer tapes) are used. A new generation of heads have been developed. The heads use the magneto-resistive effect for the read operation and a simplified inductive approach for the write operation.

Full Text

Photon Shadowing in Nuclei

Photon Shadowing in Nuclei

Ghassan Saffarini

Department of Physics, An-Najah National University

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

Photonuclear Shadowing is studied using the Glauber - generalized vector meson dominance approach. The calculation is performed using both diagonal and off - diagonal generalized vector dominance (GVMD) models. The results are compatible with experiments within the large systematic uncertainties of the available data.

Full Text

Homogeneous Catalysis of O-Silylation Reactions Using Tris (Acetylacetonato) Cobalt (III)

Homogeneous Catalysis of O-Silylation Reactions Using Tris (Acetylacetonato) Cobalt (III)

Hikmat S.Hilal

Chemistry Department, An-Najah National University, Nablus

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

Tris (acetylacetonato) cobalt (III), (Co(acac)3), has been used to catalyze o-silylation reactions of R 3 Siff (R.z.Et,Et0) with R OH (Rt-Et, i-Pr, t-.Bu and C6Hj-). No reaction has been observed at room temperature, but the reaction is apparently enhanced when carried out at a higher temperature. The rate of the reaction varies with varying the concentration of the saline or the alcohol. Using different types of alcohols and silanes greatly affects the rate of the reaction. The rate of the reaction is affected by varying the concentration of the complex (Co(acaci6)).

Full Text

Occurrence of Pythium Species in Cultivated Soils in the West Bank and Gaza Strip: A Preliminary Report

Occurrence of Pythium Species in Cultivated Soils in the West Bank and Gaza Strip: A Preliminary Report

Mohammed S. Ali-Shtayeh

Department of Biological Sciences, An-Najah National University

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

The Pythium flora of 38 soils from different sections of the West Bank and Gaza Strip was determined using a selective agar medium and a surface - soil - dilution plating technique. A total of 23 species were recovered. Sixteen of these species possessed subglobose sporangia and/or hyphal swellings and constituted 92 % of the total number of Pythium propagules. The remaining species had filamentous or lobulate sporangia. Considerable differences in population levels in the different localities were found. The Nablus locality harboured the highest mean level of Pythium propagules followed by the localities in Jenin, Bethlehem, Jericho, Tulkarm, Ramallah, Gaza Strip, and Hebron. Solis in the different localities differed also in population levels and composition of species. Associations between Pythium population levels and soil factors and agricultural practices are discussed.

Full Text

Two Methods for the Evaluation of Six Disinfectants Using Pseudomonas Aeruginosa and Serratia Marcescens as the Test Organisms

Two Methods for the Evaluation of Six Disinfectants Using Pseudomonas Aeruginosa and Serratia Marcescens as the Test Organisms

Yahya R. Faydi

Department of Biological Sciences, Nablus

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

A total of 50 isolates of Pseudomonas aeruginosa and 6 isolates of Serratia Marcescens from various clinical specimens were used in this study. The action of various commercial disinfectants on these isolates was studied using the agar and broth dilution methods. All S. Marcescens strains were inhibited by. 0.15% 0-syl or 0.44% Savlon. While P. aeruginosa strains were inhibited by 0.3% 0-syl or 0.88% Savlon. Both organisms were inhibited by 0.65% Westaspet, 0.125% Phenol, 0.5% Acriflavin or 0.25% Micro - Bac.

Full Text

Tinea Capitis in the Nablus Area

Tinea Capitis in the Nablus Area

Hisham M. Arda

Formerly Assistant Professor of Dermatology, Jordan University Hospital.

Received : 00-00-0000 , Accepted : 00-00-0000

Language: English

Abstract

During 1972 - 1979 tinea capitis patients constituted 4.2% of all new dermatology patients clinically diagnosed at the outpatient skin clinic in Ittihad Hospital and at a private clinic in Nablus. About 78.6% of tinea capitis patients were from rural areas. 76.5% of them were under the age of 10 years. In a survey at primary schools in two villages, in a refugee camp and in the city of Nablus, the incidence of tinea capitis was found to be about 15% in the village schools, 3% in the camp and 1.8% in Nablus.

Full Text