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* Corresponding author : qayyum@pinstech.org.pk ION-INDUCED SECONDARY ELECTRON EMISSION FROM 58NI AND 60NI: EVIDENCE OF SECONDARY ELECTRONS GENERATED BY THE RECOILING TARGET ATOMS Shakir Ullah
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We have measured the secondary electron yield of clean 58Ni and 60Ni bombarded with 2-10 keV Ar+ ions. It was found that secondary electron yield of 58Ni is consistently high as compared to the 60Ni. This result is not in line with the most theoretical model of kinetic electron emission, which predict strict proportionality between secondary electron yield and electronic stopping power. We have demonstrated that the measured secondary electron yield is also related to the nuclear stopping power. We thus conclude that higher secondary electron yield of 58Ni is due to the larger contribution of the recoiling target atoms to the secondary electron yield.

TOLERANCE OF DIFFERENT RICE GENOTYPES (ORYZA SATIVA L.) AGAINST THE INFESTATION OF RICE STEM BORERS UNDER NATURAL FIELD CONDITIONS M. Sarwar
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Growing of resistant varieties against insects infestation has received much attention during the recent years due to increasing awareness of insecticidal problems like environmental pollution and health hazards. Therefore, genotypic responses of 61 rice (Oryza sativa L.) genotypes (35 aromatic and 26 non aromatic) were tested against the infestation of rice stem borers. The data obtained on these genotypes on larval infestation in combination with yield were the selected criteria to assess the resistance depicted by them. The studies showed that among aromatic genotypes, ‘Khushboo-95’ gave the best yield of grain and harboured the least pest infestation (2.81% deadhearts and 1.85% whiteheads); on the other hand variety ‘Sonahri Sugdasi (P)’ harboured the highest borers attack (10.37, 19.30%) and yielded the lowest grain yield. Regarding non-aromatic genotypes, IR8-2.5-11 received least infestation (1.32%, 0.26% deadhearts and whiteheads, respectively) generating highest grain yield showing its tolerance to borer attack, in contrast, genotype IR6-252 harboured the greatest infestation (5.65%, 4.28%) and yielded minimum grain indicating its susceptibility. Accordingly, the expansion of insect resistant and high yielding varieties of rice containing moderate to high levels of resistance is a proficient approach for exploration of integrated pest management tactic.

TRANSIENT NON-THERMAL MOBILITY OF CO FOR CO-NO CATALYTIC REACTION ON HEXAGONAL LATTICE: A COMPUTER SIMULATION STUDY A. U. Qaisrani
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Monte Carlo simulation has been used to study the effect of precursor mechanism along with diffusion of N on a hexagonal lattice for CO-NO heterogeneous catalytic reaction. The reactive window gets enhanced due to the precursor mechanism. It has been also found that the diffusion of N slightly shifts the first order transition (y2) toward higher concentration of CO and therefore by including the diffusion of N the reactive window gets wider. It is observed that whenever precursor mechanism is introduced, the production of CO2 and N2 starts as soon as the CO partial pressure (yCO) departs from zero. The reactive window and production rate increases by increasing the range of precursor mobility.

PREDICTING THE VARIABILITY IN THE WAVELENGTH STRUCTURES OF THE INCOMING RADIATION DUE TO OZONE LAYER DEPLETION AT ARABIAN SEA M.A.K. Yousuf Zai
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In this communication we have investigated the variability in the wavelength structures of the radiation due to ozone layer depletion (OLD) using empirical modeling approach. A model has been developed for evaluating sea surface temperature using stratospheric ozone filter. This filter has been formulated taking into account of the ozone layer depletion (OLD) strategy for Pakistan atmospheric regions. For making predictions of various wavelength, stochastic analysis is implemented here for observing future prospects of the coming radiation. These predictions are useful for public, private and government organizations.

STUDY OF RELATIVISTIC ENERGY 207Pb PROJECTILE FRAGMENTATION ON HEAVY TARGETS G. Sher
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We investigate 158 A GeV 207Pb projectiles fragmentation interacting with Bi, Pb, Cu and Al targets using CR-39 nuclear track detectors. The stacks containing detectors and targets were exposed at SPS beam facility of CERN. After chemically etching the detectors have been scanned using optical microscope. The length of etched cones produced as a result of beam ions and the fragments in the detectors are measured.  The charge resolution (Z) in the charge region 63 < Z < 82 by this technique is achieved ~ 0.3e – 0.2e. The total charge-changing cross sections have been measured using the statistics of etched cone heights corresponding to the projectile ions and fragments produced in the fragmentation process. The measured total charge-changing cross sections are compared to those calculated using semi empirical models and those predicted by FLUKA code. Also the dependence of total cross sections on the projectile and target mass is envisaged.

TRACE ELEMENTS ANALYSIS OF CROPS AND VEGETABLES GROWN AROUND INDUSTRIAL AREAS OF FAISALABAD AND GUJRANWALA CITIES USING INAA AND AAS S.N. Husaini
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Industrial effluents pollution is a source of risk to the health of people living in developing countries such as Pakistan because untreated effluents contain health hazard toxic metals and injurious pollutants. A majority of the industries are not equipped with suitable recycling and effluent treatment plants. Therefore, in industrial cities, unrefined effluents are being used for the cultivation of crops and vegetables. Consequently, toxic metals enter our food chain and results in significant heath risks and serious diseases. In order to evaluate the concentration of toxic metals (namely As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sb and Se), crop and vegetable samples were collected from the untreated effluents irrigated areas of Faisalabad and Gujranwala regions. All collected samples were examined with the help of neutron activation analysis (NAA) and atomic absorption spectrometric (AAS) techniques. All the observed metal concentrations were higher than the reported literature values. Moreover, the highest values of toxic metals of As (0.44±0.03) and Co (0.5±0.01), Mn (45.3±2.0) and Sb (0.1±0.01), Se (1.28±0.06) and Pb (3.84±0.27) were found in tomato, bitter gourd and rice samples respectively.

COMPARISON OF AUTOREGRESSIVE (AR) STRATEGY WITH THAT OF REGRESSION APPROACH FOR DETERMINING OZONE LAYER DEPLETION AS A PHYSICAL PROCESS M.A.K. Yousuf Zai
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This communication presents a development of a comprehensive characterization of ozone layer depletion (OLD) phenomenon as a physical process in the form of mathematical models that comprise the usual regression, multiple or polynomial regression and stochastic strategy.  The relevance of these models has been illuminated using predicted values of different parameters under a changing environment. The information obtained from such analysis can be employed to alter the possible factors and variables in the process of OLD to achieve an optimum performance. This kind of analysis initiates a study towards formulating the phenomenon of OLD as a physical process with special reference to the stratospheric region of Pakistan. This piece of information establishes that Auto regressive (AR) nature of modeling OLD as a physical process is an appropriate scenario rather than using usual regression. The reported facts suggested quantitatively the phenomenon of OLD. For this purpose we have modeled this phenomenon using the data recorded at Geophysical Center Quetta during the period 1960-1999. The predictions made by this analysis are useful for public, private and other relevant organizations.

NITRITE REMOVAL FROM MARINE AQUACULTURE WASTEWATER USING ELECTROCHEMICAL PROCESS Muhammad Saleem
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The hazardous and toxic nature of some of the constituent such as nitrite in the aquaculture wastewater is of major concern. Present study focuses the removal of nitrite from the aquaculture wastewater prior to disposal. Effect of certain operational parameters such as electrode material, current density, initial pH, and electrode spacing on nitrite removal from aquaculture wastewater was elucidated. Better nitrite removal efficiency achieved when nickel used as compared to stainless steel, graphite and aluminum electrodes. Nitrite removal is positively related to the current density however, increase is up to 31.4% when current density increased from 2.5 to 9.3 mA/cm2. Further increase in current density does not improve the process efficiency. Removal efficiency of electrochemical process decreased with the increase in initial pH of test solution. However, with the passage of time this difference is diminishing. This may be attributed to the presence of higher amount of hypochloric acid which does not dissociate at lower pH values. Subsequently faster oxidation of nitrite achieved during first few minutes of test runs. Amount of available hypochloric acid reduced at high pH values and oxidation of nitrite reduced subsequently. Rate of nitrite removal found to be increased as the inter-electrode spacing decreased up to an optimal spacing of 3 cm which demonstrated highest nitrite removal. Further reduction in spacing does not augment the removal efficiency probably due to the formation of scale on cathode surface and passivation of electrode which suppressed further oxidation process.

HYDRAULIC PERFORMANCE OF TRICKLE IRRIGATION EMITTERS UNDER FIELD CONDITION Muhammad Nazeer
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The efficiency of trickle irrigation system depend the uniform distribution of water trough mechanical device, the emitter. The aim of this research study to compare and evaluate the hydraulic performance of pressure-compensating and non pressure-compensating emitters under field condition. Both types of emitters were subjected to different operating pressure (50,100,150,200 and 250KPa) of the water source. Three hydraulic performance parameters including manufacture’s coefficient of variation, hydraulic design’s coefficient of variation and total coefficient of variation were tested for pressure-compensating and non pressure-compensating emitters. Manufacturer’s coefficient of variation (CVM) values was compared with test results for both type of emitters. Hydraulic design’s and total coefficients of variation were also determined at field level. The results showed that pressure-compensating emitters  has less dependency on operating pressure as compare to non pressure-compensating ones which was further clarified by statistical analysis by their linearity at 95% confidence and prediction intervals. Hydraulic performance parameters categorized the pressure-compensating emitters in the excellent category according to ASAE standards. Designers of micro-irrigation system should bear in mind that hydraulic design coefficient of variation is less important than manufacture coefficient of variation and it is necessary that the manufacturer should to provide the detail guidelines for performance and evaluation of their products and if possible use the pressure-compensating emitters although having high prices, for future sustainability of the micro irrigation systems.

STABLE CARBON ISOTOPE  RATIO  (d13C) OF  SHALLOW MARINE BOTTOM SEDIMENT AS EVIDENCE OF POLLUTION IN  MANORA CHANNEL, KARACHI  - PAKISTAN A. Mashiatullah
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Stable isotope composition of inorganic and organic carbon fractions (measured as d13C) in the sea bottom sediments of Manora channel/Karachi harbour have been determined to track transport of pollution in the Manora channel. The principle of this application lies in the fact that d13C values of inorganic carbon (mineral fractions such as calcite, aragonite, dolomite) differs vastly from that of the organic carbon fraction of domestic and/or industrial origin in the sediments. Relatively more depleted d13C (organic) values ranging between  -30.65 to  -19.27 ‰ PDB for the organic carbon fraction were found in the Layari river outfall zone. In Manora channel mains enriched values d13C was found in sediment of Manora lighthouse (-5.0 ‰ PDB)  and Pakistan Naval Academy (-11.76 ‰ PDB) while in same zones depleted values of d13C was found  in Bhabba island (-27.31‰ PDB), Bhit Island (-26.13‰ PDB) and Boat Club area (-23.08‰ PDB)  indicating impact of domestic sewage added to the Manora channel from surrounding Islands. d13C (inorganic) fraction of sediment follow similar trend. In conclusion, this study indicates that the bottom sediments of Karachi Harbour and Layari river outfall zones are mainly polluted with organic waste of domestic origin derived from Layari river.

NANOCOMPOSITE SURFACES – A REVIEW T.I. Khan
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The development of nanocomposite surfaces offers significant improvements in mechanical properties over conventional microstructured surfaces. However, to develop nanostructured surfaces for abrasive wear resistant applications still remains a challenge. This paper gives an overview of some of the more successful spraying techniques such as High Velocity Oxy-Fuel (HVOF) spraying that have been used to deposit thick nanostructured WC-Co based coatings. The retention of the nanostructure developed in the feedstock powders through control of spraying parameters has some limited success in preventing decarburization of the WC nano-sized dispersion in the Co matrix. The use of a novel duplex Co-coated powder has the effect of eliminating decarburization and this is reflected in a noticeable increase in mechanical and wear resistant properties of the final coating. Cold gas dynamic spraying techniques have also been used to control the final composition and grain structure of WC-Co based coatings and the corresponding properties changes are compared and discussed.

Conditionally Accepted Papers

INHIBITION MECHANISM OF DIAMINE BASED CORROSION INHIBITOR IN SIMULATED WATER. I. Reza
The objective of this study is to investigate the inhibition efficiency of a diamine based corrosion inhibitor for low carbon steel in synthetic cooling water at a temperature of 25oC.The studies had been carried out by using weight loss measurement, Electrochemical (Potentiodynamic Polarization and Electrochemical Impedance Spectroscopy) and microscopic techniques. This inhibitor established good inhibition efficiency at a concentration of 30 ppm. Outcomes obtained, divulged that inhibition takes place by adsorption of the inhibitor on metal surface without altering the mechanism of corrosion process. The results obtained followed Langmuir adsorption isotherm.

AC PROPERTIES OF Ca DOPED Mn0.5Zn0.5Fe2O4 H. M. Iftekhar Jaim
In this paper, we studied the ac properties of 1.25% Ca doped (on weight basis) Mn0.5Zn0.5Fe2O4 prepared by standard solid state reaction method. Frequency dependent complex permeability, complex permittivity, complex impedance, conductance and quality factor from 1MHz to 1.8GHz of this spinel ferrite were measured in the Agilent 4291B RF impedance analyzer. The ac conductivity mechanism is discussed on the basis of a hopping electron model. The ac permeability is discussed with the present theoretical models for polycrystalline spinel ferrites where as anomalous ac permittivity is observed in a certain frequency range due to the presence of both p-type and n-type carriers. It is found that Ca doping of such minute level enhances the impedance reducing the eddy current loss at grain boundaries at higher frequency region without affecting the other magnetic properties.

EFFICACY OF SOME NATURAL HOSTS ON THE DEVELOPMENT OF CHRYSOPERLA CARNEA (STEPHENS) IN THE LABORATORY N. Ahmad
The production of quality insects under laboratory conditions is a prerequisite for the successful biological control of any insect pests. It is well documented that maintenance of insect colonies remains necessary, but often costly. Therefore, biology and feeding potential of the predator, Chrysoperla carnea (Stephens) was studied on different hosts with particular reference to cotton crop. Various hosts viz., aphids (nymphs/ adults) and the eggs of cotton bollworms were used for the rearing of C. carnea and compared with the factitious host, angoumois grain moth (Sitotroga cerealella) eggs on which the culture of the predator is being maintained for the last many generations at the laboratory. The studies indicated that larval and pupal duration of the predator was significantly affected due to the change of the hosts and the total developmental period was significantly shorter when the predator was offered aphids for feeding. The fecundity and fertility of the predator were also higher on aphids followed by spotted bollworms and angoumois grain moth eggs. Hatchability and sex ratio were not affected due to the change of the hosts. Based on the studies aphids appeared to be the most promising host for mass rearing of the predator. Further, successful predation of the cotton bollworm eggs manifested the potential of C. carnea for the management of cotton bollworms in the field.

STUDIES ON THE COMPATIBILITY OF PYRETHROID AND DIFFERENT CONCENTRATIONS OF NEEM SEED EXTRACT WITH TRICHOGRAMMA CHILONIS (ISHII) (HYMENOPTERA: TRICHOGRAMMATIDAE) M. H. Khan
The Trichogramma chilonis (Hymenoptera: Trichogrammatidae) is an important egg parasitoid reported to reduce the lepidopteron pest populations considerably and often released argumentatively in Integrated Pest Management programs. Studies on the compatibility of Pyrethroid (Ripcard 0.5%) and different concentrations of neem (Azadirachta indica) seed extract with T. chilonis was conducted. Among different concentrations of neem seed extract (4%, 2%, 1%, 0.5% and 0.25%), maximum mortality (68.29%) of Trichogramma was recorded with 4% neem seed extract and minimum (35.83%) with 0.25% neem seed extract. However, the highest mortality (97.52%) of Trichogramma was recorded with Ripcard 0.5%. Emergence time was non significantly different in all treatments of neem seed extract but was significantly different from Ripcard where the emergence time was 9.75 days. Longevity and sex ratio was also non significantly different in all treatments of neem seed extract. It can be concluded that neem seed extract up to 4% concentration can be included in IPM to protect T.  chilonis as biological control agent.

A MULTIAGENT SYSTEM BASED AUTOMATED PROFILING MODEL TO AVOID INSIDER THREAT G. Ali
The proposed model builds and maintains the profile of all insiders to detect and avoid threat. Software agents are autonomously working to record all activities of the authenticated users. The profile is compared with the policy of the organization and insider’s profile is marked acceptable or suspicious. This will lead to a proper mechanism to protect organizations assets against threat. The model is generic, adaptable and works in most of the organizations. It follows the renowned agent standard of FIPA as agents modeled on other platforms can interact with the agents developed on the proposed model.

TOTAL PHENOLIC COMPOUNDS AND ANTIOXIDANT ACTIVITY OF JAMUN FRUIT (EUGENIA JAMBOLANA) PRODUCTS M. Shahnawaz
In this study, total phenolic contents and antioxidant activity in various products of jamun fruit (Eugenia jambolana) cultivars of Sindh i.e. V1-improved and V2-indigenous were determined.  Five Products made from each jamun fruit cultivar such as jam, squash, ready-to-drink juice, pulp powder and seed powder. Fruit cultivars were endogenous to the typical tropical region of Sindh-Pakistan. Total phenolic content of the products were analyzed by Folin-Ciocalteu colorimetric method, whereas, the total antioxidant activity analyzed by using the 2, 2-diphenil-1-picrylhydrazyl radical scavenging capacity (DPPH) assays. The highest total phenolic content and antioxidants were observed in freeze dried seed powder (mg gallic acid equivalent (GAE) g-1 dry weight (DW)), while the lowest content was found in squash of both the cultivars. The present study demonstrates the potential value of jamun fruit for nutritional and pharmaceuticals supplements.

RURAL AREAS ARE THE RESERVIOR OF HEPATITIS C VIRUS K. Saleem
A randomized cross-sectional study was conducted in the rural area of Islamabad having a population of fifteen thousand from May 2009 to August 2009 to study the prevalence of Hepatitis C virus in rural areas and to describe its modes of transmission. Two hundred healthy volunteers were randomly screened for Hepatitis C antibodies. The blood samples were send to PCH for chromatographic method after they filled a detailed questionnaire to determine their demographic data and possible risk factors The prevalence of  16.5% was recorded  in rural areas of Islamabad with highest seropositivity  among females (63%) than males(37%) and  use of non disposable syringes for intravenous therapies  (82.5%) as the major mode of transmission, dental treatment( 62.5%), and ear piercing( 61%) being  the other major  routes of viral transmission.

EMS INDUCED MUTATIONAL VARIABILITY IN VIGNA RADIATA AND VIGNA MUNGO M. Imran Kozger
Ethylmethane sulphonate (EMS) has been long considered as a potential chemical mutagen for inducing genetic variability in crop plants. This study tries to elucidate out the effect of different doses (0.1% to 0.4%) of EMS on the two species of genus Vigna viz; radiata and mungo in M1 and M2 generations for isolation of probable mutants and their respective comparative studies. Selection of mutants is based upon the variation in genetic parameters for yield and certain yield contributing characters. The comparative studies on the estimation of total seed protein content and nitrate reductase activity (EC 1.7.99.4), NRA, in both generations of these two species have also been studied in order to reveal the potentiality of mutants isolated for raising M3 generation. In the present study doses of EMS were found to be very effective in generating mutation for higher yield in both species and there was a linear correlation of the total protein content and NRA to the total plant yield. Probable application of protein and DNA profiling for isolating mutants in M3 generation, possibly to be accomplished as a harvest of year 2010 kharif season, the accuracy of the selected mutants in M2 generation would be satisfactorily evaluated. This would help in isolating wide range of mutant pools accurately to large extent in shorter duration.