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Corrosion by a Heavy Metal Oxide Glass

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Journal of Materials Science & Technology 2005年第2期21卷 243-245页

作者： B.B.Rana Department of Engineering Materials University of Sheffield Sheffield S1 4DU UK PCSIR Laboratories Complex LahorePakistan

Melts of lead bismuth gallate compositions are highly corrosive and attack on crucibles of different materials. In the present study, corrosion by a base glass (50PbO-30Bi2O3-20Ga2O3 in mole fraction) melted using different crucibles and the effect on UV-VIS and IR edges were studied. By melting the base glass in platinum/2% rhodium, gold zirconia and alumina crucibles showed less effect on the IR edge and therefore shifted the infrared edge to longer wavelength, whereas silica crucible contaminated the glass, causing a severe deterioration in the infrared and hence shifted infrared edge to much shorter wavelength. In the UV-VIS region, base glass melted in platinum/2% rhodium crucible shifted the edge to the longest wavelength whereas silica crucible shifted the edge to shorter wavelength. The contaminants from gold, zirconia and alumina crucibles caused the UV-VIS edge of the base glass to lie between the two extremes of Pt/2% Rh and SiO2 crucibles. The glasses melted in above mentioned crucibles were also characterized with inductively coupled plasma spectroscopy (ICP) analysis to measure the level of contamination from the crucibles. Depending upon crucible used, the colors of glasses obtained ranged from red to yellow.

关键词： Oxide glass Corrosion Crucible

Weathering and accumulation of trace elements in the soils of the Porali Plain, Balochistan: repercussions in agriculture

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Acta Geochimica 2024年第2期43卷 214-234页

作者： Maria Kaleem Erum Bashir Shahid Naseem Tahir Rafique Bushra Shahab Department of Geology University of KarachiKarachi 75270Pakistan Applied Chemistry Research Centre PCSIR Laboratories ComplexKarachi 75280Pakistan

This study is theﬁrst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by multi-variate analysis based on geochemical *** outcomes of this study are expected to help farmers in soil manage-ment and selecting suitable crops for the ***-ﬁve soil samples were collected,mainly from the arable land of the Porali *** drying and coning-quarter-ing,soil samples were analyzed for major and trace ele-ments using the XRF technique;sieving and hydrometric methods were employed for granulometric ***-mated data were analyzed using Excel,SPSS,and Surfer software to calculate various indices,correlation matrix,and spatial *** granulometric analysis showed that 76%of the samples belonged to loam types of soil,12%to sand type,and 8%to silt *** indices:CIA,CIW,PIA,PWI,WIP,CIX,and ICV were calculated to infer the level of *** indices reﬂect mod-erate to intense weathering;supported by K_(2)O/AI_(2)O_(3),Rb/K_(2)O,Rb/Ti,and Rb/Sr *** of the geo-ac-cumulation and Nemerow Pollution indices pinpoint rela-tively high concentrations of Pb,Ni,and Cr concentration in the *** correlation matrix and Principal Compo-nent Analysis show that the soil in this study area is mainly derived from the weathering of igneous rocks of Bela Ophiolite(Cretaceous age)and Jurassic sedimentary rocks of Mor Range having SEDEX/MVT type *** may result in the undesirable accumulation of certain trace elements which adversely affects crops.

关键词： Weathering indices Pollution indices Accumulation Repercussions Trace elements Multivariate analyses Porali Plain Balochistan

Chemical composition and antioxidant activity of certain Morus species

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第12期11卷 973-980页

作者： Mohammad IMRAN Hamayun KHAN Mohibullah SHAH Rasool KHAN Faridullah KHAN Institute of Chemical Sciences University of Peshawar Department of Chemistry Islamia College University Pakistan Council of Scientific & Industrial Research (pcsir) laboratories Complex

In the present work,the fruits of four Morus species,namely Morus alba (white mulberry),Morus nigra (black mulberry),Morus laevigata (large white fruit),and Morus laevigata (large black fruit),were analyzed for proximate composition,essential minerals,and antioxidant *** this purpose,the ripe fruits were collected from the northern regions of *** major nutritional components moisture,ash,lipids,proteins,fibres,carbohydrates,and total sugar) were found to be in the suitable range along with good computed *** dry weight,pH,and titratable acidity (percent citric acid) were (17.60±1.94)–(21.97±2.34) mg/100 g,(3.20±0.07)–(4.78±0.15),and (0.84±0.40)%–(2.00±0.08)%,*** riboflavin (vitamin B2) and niacin (vitamin B3) contents were recorded in all the fruits,while ascorbic acid (vitamin C) was in the range from (15.20±1.25) to (17.03±1.71) mg/100 g fresh weight (FW).The mulberry fruits were rich with regard to the total phenol and alkaloid contents,having values of (880±7.20)–(1650±12.25) mg/100 g FW and (390±3.22)–(660±5.25) mg/100 g FW,*** quantities of essential macro-(K,Ca,Mg,and Na) and micro-(Fe,Zn,and Ni) elements were found in all the fruits.K was the predominant element with concentration ranging from (1270±9.36) to (1731±11.50) mg/100 g,while Ca,Na,and Mg contents were (440±3.21)–(576±7.37),(260±3.86)–(280±3.50),and (240±3.51)–(360±4.20) mg/100 g,*** decreasing order of micro-minerals was Fe>Zn>*** radical scavenging activity of methanolic extract of fruits was concentration-dependent and showed a correlation with total phenolic constituents of the respective *** on the results obtained,mulberry fruits were found to serve as a potential source of food diet and natural antioxidants.

关键词： Mulberry fruits Chemical composition 2 2-diphenyl-l-picrylhydrazyl (DPPH) radical scavenging activity Nutritional value. Pakistan

Chemical Kinetic Aspects of Solid State Reaction Producing Wollastonite from Rice Husk Silica and Limestone

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Journal of Materials Science & Technology 2001年第2期17卷 243-246页

作者： M.S.Nizami pcsir laboratories Complex, Lahors, Pakistan M.Z.Iqbal Punjab University, Institute of Chemistry, Lahors, Pakistan pcsir Lab. Complex Lahore Pakistan

An industrial mineral wollastonite (CaSiO3) was produced under solid state conditions from rice husk silica and limestone. Reaction was carried out at 900'C to 1300'C for 1 h. The product batches were subjected to XRD and chemical analysis techniques specific for wollastonite. Mole fractions of different product batches were calculated on the basis of accumulated data to study the kinetics. Specific rate constants and reaction rate were also found out. Various probable models of mechanism for reaction were considered and testified with the laid down criterion for suggesting the suitable one. The resulting data were treated with Arrhenius equation as well and activation energy was calculated--therefrom. In addition to finding it's value from the slope of Arrhenius curve, an alternate method was also applied for this purpose. Both of the values were observed to be comparable. The activation energy required for performed reaction was found to be almost one third of that reported for synthesizing CaSiO3 by using quartz. This referred to the economical preparation of wollastonite by using rice husk as a source of silica instead of quartz.

关键词： Chemical Kinetic Aspects of Solid State Reaction Producing Wollastonite from Rice Husk Silica and Limestone rate

Antibacterial activities of some selected plant extracts of local herbal medicines in Lahore-Pakistan

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Journal of Chinese Pharmaceutical Sciences 2012年第3期21卷 278-282页

作者： Fouzia Noreen Naqi Hussain Muhammad Zaheer Salma Rahman Applied Chemistry Research Center PCSIR Laboratories ComplexFerozepur RoadLahore 54600Pakistan

The antibacterial activity of methanol and acetone extracts of five plant extracts being utilized for the cure of different ailments in Pakistan was *** extracts of Curcuma zedoaria,Ipomea turpethum,Sphaeranthus indicus,Terminalia chebula and Tricholepis glaberrima were tested against seven different bacterial strains by well diffusion method and microdilution *** pattern of zone of inhibition varied with the plant extracts,the solvent used for extraction and organisms *** extracts(20 mg/mL) were used to evaluate antibacterial *** zone of inhibition exhibited by methanol extracts varied between 11 mm and 32 mm while those of acetone extracts varied between 9 mm and 25 mm *** minimum inhibitory concentration(MIC) exhibited by methanol extracts ranged between(18.4-51.1) mg/*** methanolic extracts showed more activity than the acetone extracts against tested organisms except for *** plants were also analyzed for their elemental composition using atomic absorption spectrophotometer to explore natural sources of essential elements that can be utilized for medicinal purposes.

关键词： Minimum inhibitory concentration Minimum bactericidal concentration Elemental composition Atomic absorption spectrophotometer

Synthesis, X-ray Crystallographic Analysis and Bioactivities of α-Aminophosphonates Featuring Pyrazole and Fluorine Moieties

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Chinese Journal of Structural Chemistry 2014年第11期33卷 1673-1682页

作者：洪艳平上官新晨 IQBAI Zafar 尹小莉 Jiangxi Key Laboratory of Natural Product and Functional Food College of Food Science and Engineering Jiangxi Agricultural University pcsir laboratories Complex Library of Jiangxi Agricultural University

A series of novel -aminophosphonates containing pyrazole and fluorine moieties was designed and synthesized through ultrasonic-assisted condensation and solvent-free addition reactions. Their structures were verified by IR, ^1H NMR, ^13C NMR and elemental analysis. The crystal structure of diethyl[（4-cyano-1H-pyrazol-3-ylamino）（3,5-difluorophenyl）methyl]phosphonate（4a, C15H17F2N4O3P） was determined by single-crystal X-ray diffraction. Compound 4a crystallizes in the triclinic system, space group P1 with a = 8.381（3）, b = 10.103（5）, c = 11.268（3） A, α= 83.772（19）, β= 74.726（19）, γ= 70.964（18）, V = 869.9（6） 3, Mr = 370.30, Dc = 1.414 g/cm^3, Z = 2, F（000） = 384, = 0.200 mm^-1, MoKa radiation（ = 0.71073 ）, the final R = 0.0487 and w R = 0.0823 for 1582 observed reflections with I 〉 2（I）. X-ray diffraction analysis reveals that there are two planes in 4a, and the dihedral angle is 71.51°. Two intermolecular hydrogen bonds and a face-to-face … stacking interaction are observed in the crystal structure. The compounds were evaluated for their antifungal, antiviral and antitumor activities, respectively. Among them, 4b, 4c, 4g and 4h exhibit good activities on Sclerotium rolfsii Sacc at 200 μg/m L, while 4b, 4c, 4f and 4g possess good anti-TMV activities at 500 μg/m L. Unfortunately, all of the compounds showed weak antitumor activities.

关键词： α-aminophosphonate pyrazole and fluorine crystal structure bioactivities synthesis

Physico-chemical analysis and antimicrobial potential of Apis dorsata,Apis mellifera and Ziziphus jujube honey samples from Pakistan

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Asian Pacific Journal of Tropical Biomedicine 2014年第8期4卷 633-641页

作者： Hira Fahim Javid Iqbal Dasti Ihsan Ali Safia Ahmed Muhammad Nadeem Department of Microbiology Qauid-i-Azam University IslamabadPakistan pcsir Research laboratories Thokar Niaz BaigLahorePakistan

Objective:To evaluale physico-chemical properties and antimicrobial potential of indigenous honey samples against different reference strains including Escherichia coli ATCC *** aerogenes ATCC *** aeruginosa ATCC *** subtilis *** aureus ATCC *** typhi ATCC 14028,Klebsiella pneumonia ATCC *** niger ATCC *** oligasparus *** albicans ATCC14053 and Candida utilis ATCC ***:By using standard methods samples were evaluated for their antimicrobial properties including additive effect of starch and non—peroxidase activity,antioxidative properties(phenol contents,flavonoid contents,1,1-diphenyl-2-pierylhydrazyl radical scavenging activity).Prior to this evaluation,complete physico-chemical properties including pH,color,ash contents,protein contents,moisture contents,hydroxymethyl furfural contents,total sugar contents,reducing sugar and non-reducing sugar contents were ***:Relatively higher ash contents were found in the Siddar honey i.e.(0.5900±0.0336)%and small honey showed relatively higher protein contents i.e.(777.598±9.880) mg/*** moisture contents of tested honey samples ranged between 13.8%—16,6%,total sugar contents foam 61.672%-72.420%and non-reducing sugar contents from 1.95%—3.93%.Presences of phenolic contents indicate higher antioxidant potential of these honey *** bacteria showed clear inhibition zones in response to tested honey samples whereas fungi and yeast showed inhibition at higher concentrations of these honey *** Escherichia *** *** *** aeruginosa and Aspergillus niger,overall the small honey showed the higher activity than other honey ***:Physico-chemical analysis of honey samples confirmed good quality of honey according to the standards set by European Union Commission and Codex Alimcntarius *** of these honey samples confirms antim

关键词： Ziziphus jujube honey Antimicrobial properties Non-peroxidase activity Antioxidative properties

A perusal on the correlation of pesticide application on tobacco growing in the districts of NWFP-Pakistan and cancers incidence

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Chinese Journal Of Geochemistry 2006年第B8期25卷 187-188页

作者： Jehangir Shah Abdur Rahman Mumtaz Khan Khan pcsir laboratories Complex Peshawar Pakistan

Comparison between Pigment Printing Systems with Acrylate and Butadiene Based Binders

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Journal of Analytical Sciences, Methods and Instrumentation 2012年第2期2卷 87-91页

作者： Mansoor Iqbal Javaid Mughal Munazza Sohail Arsheen Moiz Kamran Ahmed Khalil Ahmed Applied Chemistry Research Centre PCSIR Laboratories Complex Karachi Pakista Applied Chemistry Research Centre PCSIR Laboratories Complex Karachi Pakistan

Pigment printing was carried out on lab scale by simple screen-printing techniques. By the application of acrylate and butadiene based binder, the crocking fastness, formaldehyde release and PVC migration of fabric printed with Imparon red KB pigment was evaluated. The effect of curing time on K/S values was also investigated. It has been found that butadiene based binder shows good performance in terms of crocking fastness, formaldehyde release and PVC migra-tion. It has also been observed that by increasing the binder concentration, the release of formaldehyde decreased and by increasing the curing time, the K/S values of printed fabric were decreased.

关键词： Printing Pigment Binder Acrylate Butadiene