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ABSTRACT A series of anthracene-based microporous polymers (AMPs) bridged by imide links were successfully prepared by conventional nucleophilic substitution reaction between several 9,10-dihydro-9,10-ethanoanthracenes and cheaper 2,3,5,6-tetrachlorophalonitrile (instead of fluoro-monomer)1. AMPs display a BET surface area in the range of 811-988 m2 g–1, and reversibly adsorb 1.59 wt. % H2 at 1.09 bar/77 K. The enhanced microporosity, in comparison to other organic microporous polymers prepared from (5,5’,6,6’-tetrahydroxy-3,3,3’,3’-tetramethylspirobisindane)2 originates from the macromolecular shape of framework, as dictated by the anthracene units, which helps to reduce intermolecular contact between the extended planar struts of the rigid framework. The impressive hydrogen adsorption capture of these materials verified by Horvath?Kawazoe (HK) and NLDFT analyses of low-pressure nitrogen adsorption data.

In this study, histological examination of the testicles and cellular tissue changes of sperm cells in the spermatogenesis phase of zebrafish are aimed. In this respect; the microscopic structure of the testicles, the position and form of the cells belonging to spermatogenic string, tissue-generating structural cells, and these organisms are examined with the light microscope. All the phases of spermatogenesis are classified as spermatocytogenesis, meiosis and spermiogenesis taking all the phases and histological development of the cells into consideration. All the cells belonging to these phases are seen in separate groups in seminiferous tubules. It is found out that there are somatic cells around spermagony. And spermatogenic cells return into spermatogenic string cells respectively (primer spermatocyte, secondary spermatocyte, spermatide and sperm organisms) by meiosis.

The aim of this paper is to investigate the linkage between macroeconomic variables (inflation rate, exchange rate and interest rate) on stock market returns in Pakistan. We used the Pakistan Karachi stock exchange 100 index as a proxy to represent the stock market returns and the interest rate, inflation rate, and exchange rate were used as the macroeconomic variables. Secondary data was collected from the period of January 2007 to December 2012. A Multiple Linear Regression was performed for the purpose of data analysis. The study showed that there is weak connection between macroeconomic variables and stock market returns. The research validates the findings of earlier studies as well as conclusions and recommendations are discussed.

This paper focuses on anti-reflective coatings on monocrystalline silicon solar cells and the impact of thickness and refractive index on reflectivity. The reference wavelength of silicon is 700nm, with its optimum refractive index (n = 3.7838) and a surface reflectivity of 33%. The calculations were based on values of layer thickness and refractive indices that meet the chosen phase and amplitude conditions, namely (HfO2), (MgF2); (SiOxNy), (SiOx), (Si3N4) and (SiNx:H). Numerical simulations have shown that low reflectivities at the surface of the single-layer coated planar cell can be obtained (3% with Si3N4) and (2% with HfO2). Multilayers such as MgF2/SiNx:H/Si, give a very low reflectivity of around 1%.

Adders are the most vital part of any digital system. Providing an efficient adder design which satisfies the tradeoff between speed and space aides in increasing the performance of the system. parallel prefix adders are the ones widely used in digital design. This is primarily because of the flexibility in designing the adders. Brent kung adder is low power adder, as it uses minimum circuitry and also decrease the speed and memory to obtain the result. The 16-bit design is extended to 32-bit, implemented in the physical level.

In order to improve the English teaching effect, we adopt the information system as the assistance with the English teaching. By the online function and automatic management with the system software, teachers and students got more communication and achieved more effective results, especially on spoken English. The practice implies that it is feasible and effective to apply the information system to the English teaching.

Friction Stir Welding, a relatively new welding process, was developed in 1991 at The Welding Institute near Cambridge, England. In this process parts are mated together, rigidly fixtured, and joined in solid-state by forcing a rotating tool into the joint, and traversing that tool along the joint. This process creates weldments with properties comparable to the base metal and in most cases superior to traditional fusion welding techniques. During the Friction Stir Welding (FSW) process, the forging forces under the tool plastically deform the material, “stirring” the material around the tool pin and against the tool shoulder, thus joining the mated parts together. This process induces large shear forces in the plastically deforming material, raising the temperature of the material to approximately 80% of the melting temperature. The FSW process parameters such as tool rotational speed, welding speed, axial force, etc. play a major role in deciding the weld quality. In present investigation, the effect of processing parameters on mechanical properties of AA6082-O joints produced by friction stir welding was analyzed. Different welded specimens were produced by varying rotating speeds of the tool as 900 & 1200 rpm and by varying welding speeds as 50 & 63 mm/min. The FSW joints mechanical properties of the material such as yield strength, tensile strength and percentage of elongation were evaluated by means of tensile tests.

The purpose of this study is to determine the university student’s intention toward doing job or business. This study is based on primary data in which data collected from 150 students of different university of Lahore District, Pakistan. We use self administrated approach. The response rate is 86%. 64% of the students decide to do job and 33% decided to start their own business. 80% female are interested to do job, and 54% male willing for job because female are less risk taker rather than male. Female performance more to do a job rather than business because male to do business rather than job.

The national water policy of India is not concomitant with its land use pattern. The countries constituting the SAARC recognise trade and economic relationships among the member countries of Pakistan, Bangladesh, Srilanka, Nepal, Bhutan and Maldives but does not attempt at a comprehensive land and water resources policy for the region. But the rivers flowing in the SAARC region are not confined to national boundaries. In a similar manner no such policy exists among the member states of India. Population growth, unchecked urban migration against limited land and water resources has led to piecemeal and short term approaches to management rather than attempting at holistic global solutions in land and water sharing among the member states of India. For instance in Tamilnadu, water starved state, sharing of waters from the 45 rivers from neighbouring Kerala state has not been successful so far. With the result these rivers originating in Kerala flow waste to Arabian sea. One of the major drawbacks occurring in these exercises is the Tamilnadu has so far been concerned at its own interest in procuring water from Kerala rather than attempting to point out the benefits accruing to kerala which has no space to store the water. Research done in this regard reveal that benefits accruing to Kerala state are substantial in comparison with Tamilnadu.

The aim of this study was to establish the relationship between the Stature and Popliteal Height Sitting, PHS. 161 male occupational bus drivers were randomly selected for anthropometric characterization of Stature and PHS using standard measuring equipment. The data were analyzed using SPSS 16.0 and Design-Expert 6.0.8. Then regression model was used to estimate PHS. The model shows that there is a linear relationship between the Stature and PHS with coefficient of determination (R2) of 0.8258 (p < 0.0001). The model mitigates time required for gathering anthropometric data. Designers would find this as a huge working tool for adequate productions.