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产胞外多糖乳球菌的优化培养

中国乳品工业 2008年第7期36卷 25-28页

作者：王艳萍冯武 zaheer AHMED 天津科技大学食品工程与生物技术学院天津300457

以苯酚硫酸法测定乳酸乳球菌乳酸亚种WH-C1在不同培养基中的胞外多糖合成量,试验以WHEY作为基础培养基,比较了添加不同碳源、氮源对EPS合成的影响,并采用正交实验L9(34)对碳源、氮源的添加量及培养基初始pH进行了优化,确定最佳组合为:... 详细信息

以苯酚硫酸法测定乳酸乳球菌乳酸亚种WH-C1在不同培养基中的胞外多糖合成量,试验以WHEY作为基础培养基,比较了添加不同碳源、氮源对EPS合成的影响,并采用正交实验L9(34)对碳源、氮源的添加量及培养基初始pH进行了优化,确定最佳组合为:葡萄糖添加量15 g/L,胰蛋白胨添加量5 g/L,培养基初始pH值为6.5。研究了不同培养温度和接种量条件下该菌株的EPS合成曲线,结果表明温度对发酵液中EPS总积累量的影响较大,通过本研究确定了乳酸乳球菌乳酸亚种WH-C1最佳培养条件为:培养温度25℃,接种量为2%(体积分数),培养时间32 h,EPS合成量为325.8 mg/L。

关键词：胞外多糖优化培养基培养条件

Few-layer Ti_(3)CN MXene for ultrafast photonics applications in visible band

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Journal of Materiomics 2023年第1期9卷 44-55页

作者： Zixin Yang Qi Yang Yulin Tian Xianghe Ren Chun Li Yuqian Zu Syed zaheer Ud Din Lingfeng Gao Jian Wu Hualong Chen Han Zhang Jie Liu Jingliang He Abdullah GAl-Sehemi International School for Optoelectronic Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material TechnologyMinistry of Edu-cationHangzhou Normal UniversityHangzhou311121China College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha410073China Institute of Microscale Optoelectronics College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China Shandong Provincial Engineering and Technical Center of Light Manipulations and Shandong Provincial Key Laboratory of Optics and Photonic Device chool of Physics and ElectronicsShandong Normal UniversityJinan250358China State Key Laboratory of Crystal Materials Shandong UniversityJinan250100China Research Center for Advanced Materials Science(RCAMS) King Khalid UniversityAbha61413Saudi Arabia Department of Chemistry College of ScienceKing Khalid UniversityAbha61413Saudi Arabia

Ti_(3)CN,as a typical hetero-MXene,has attracted tremendous attention for its unique ***,its ultrafast photonics applications are still ***,the few-layer Ti_(3)CN MXene was successfully prepared by selective etching and molecular delamination *** nonlinear optical response of few-layer Ti_(3)CN MXene at 640 nm was studied using the open-aperture Z-scan *** asprepared Ti_(3)CN MXene sample exhibited excellent nonlinear saturable absorption characteristics,resulting in the nonlinear absorption coefficient b of4.05×10^(-2)cm/GW,which was one order of magnitude larger than that of black phosphorus(BP)and molybdenum disulfide(MoS_(2)).For the optical modulation applications of few-layer Ti_(3)CN MXene,passively Q-switched(PQS)solid-state visible lasers based on Ti_(3)CN saturable absorber(SA)at 522 nm,607 nm,639 nm,and 721 nm were successfully ***,a Ti_(3)CN-based stable passively mode-locked Pr:YLF red laser was also successfully achieved with a pulse duration of 30 ps,and the corresponding repetition rate was 73.1 *** optical modulation device based on few-layer Ti_(3)CN MXene shows good *** work demonstrates that the tremendous prospects of the few-layer Ti_(3)CN MXene as a visible optical modulation device in ultrafast photonics applications.

关键词： Ti_(3)CN MXene Z-scan Saturable absorber Optical modulator Pulsed visible lasers

Population Status, Threats and Conservation of the Spotted Pond Turtle;Geoclemys Hamiltonii (Gray, 1830) (Geoemydidae) of Pakistan

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Journal of Zoological Research 2021年第1期3卷 29-37页

作者： Amtyaz Safi Muhammad zaheer Khan Roohi Kanwal Hans-Volker Karl Department of Zoology(Wildlife Section) University of KarachiKarachi-75270Pakistan. Friedrich-Schiller-University of Jena Dpt.Pre-historic and Early historic ArcheologyLöbdergraben 24a07743 JenaGermany

In the present work on population status,threats and conservation of the spotted pond turtle;Geoclemys hamiltonii(Gray,1830)(Geoemydidae)was conducted in Thatta,Sujawal and Badin districts of Sindh province of Pakistan.A total number of 277 live specimens of *** from southeast province(Sindh)of Pakistan have been collected from different water bodies and sites in three consecutive year’s i.e *** population status of *** has recorded as decreasing in Sindh due to habitat destruction,eutrophication,agricultural farming and some other anthropogenic *** species is mostly used as pet and the poachers mostly carrying this species for trade in East Asian *** globally illegal trading hubs of this species are Bangkok,Taiwan and Hong *** and powerful actions and efforts are needed to raise awareness of smuggling of wildlife,with a specific need of formal memorandums of understanding(MOUs)are strongly encouraged south Asian and east Asian countries to control illegal trade between the countries and territories along the trade route of Bangladesh,India,Pakistan,Thailand,Hong Kong and Taiwan to improve cross border enforcement.

关键词： Population status Threats Conservation Geoclemys hamiltonii

Qualitative and Quantitative Estimation of Hydroquinone in Skin Whitening Cosmetics

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Journal of Cosmetics, Dermatological Sciences and Applications 2012年第3期2卷 224-228页

作者： Saima Siddique Zahida Parveen Zeeshan Ali Muhammad zaheer PCSIR Labs Complex Lahore Pakistan

Hydroquinone has been used for decades as a skin lightening agent. Its use in cosmetics has been banned as a result of skin problems including contact dermatitis and ochronosis. A total of 22 samples of different skin whitening cosmetics were collected from local market. They were analyzed by using thin layer chromatography and HPLC for qualitative and quantitative determination of their hydroquinone contents. The hydroquinone was extracted from samples by using 96% ethanol and was subjected to TLC analysis. Eleven out of 22 samples were found to contain hydroquinone. The HPLC analysis showed the concentration of hydroquinone ranged from 0.002% to 0.092% in the cosmetic samples.

关键词： Hydroquinone HPLC Whitening Cosmetics Thin Layer Chromatography

Stability Analysis of Electromagnetic Ordinary and Extraordinary Modes

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Journal of Modern Physics 2016年第10期7卷 1120-1131页

作者： N. Noreen S. zaheer H. A. Shah Forman Christian College Chartered University Lahore Pakistan Government College University Lahore Pakistan

By using kinetic theory, we derived the general dispersion relations for ordinary mode (O-mode) and Extra-ordinary mode (X-mode) in anisotropic magnetized plasma. The effects of energy anisotropy, magnetic field to density ratio () and the plasma beta on the propagation characteristics, have been analyzed. The stability analysis and the growth rates have been presented. The marginal threshold condition for oscillatory and purely growing mode has been obtained for higher harmonics and we have also calculated their growth rates in terms of plasma beta and energy anisotropy . The X-mode satisfies the instability condition according to difference of geometry with the O-Mode. These modes are important for spherical tokamaks, and their coupling leads to the generation of the Bernstein mode, which causes the heating effects.

关键词： Instabilities Growth Rate Anisotropy

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一株产黏特性的乳酸菌及其应用研究

中国食品添加剂 2009年第1期20卷 91-95,81页

作者：王艳萍李超张玢 zaheer Ahmed 天津科技大学食品工程与生物技术学院天津300457

利用苯酚硫酸法从分离自西藏Kefir粒的11株乳酸菌中筛选得到了一株胞外多糖(EPS)产量较高的乳酸菌KF5,经生理生化实验及分子遗传学鉴定该菌株为植物乳杆菌(Lactobacillus plantarum)。生物学特性表明KF5具有较好的耐酸性以及一定的胆盐... 详细信息

利用苯酚硫酸法从分离自西藏Kefir粒的11株乳酸菌中筛选得到了一株胞外多糖(EPS)产量较高的乳酸菌KF5,经生理生化实验及分子遗传学鉴定该菌株为植物乳杆菌(Lactobacillus plantarum)。生物学特性表明KF5具有较好的耐酸性以及一定的胆盐耐受力,该菌株具有较强的产胞外多糖的能力。将添加有KF5的发酵乳与传统发酵乳相比较,其发酵乳的特性(产酸量、乳清析出率、黏度)良好,可作为取代植物或动物增稠剂使用。

关键词： EPS 筛选鉴定特性

Evaluation of Tomato Lines against Septoria Leaf Spot under Field Conditions and Its Effect on Fruit Yield

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Agricultural Sciences 2016年第4期7卷 181-186页

作者： Zishan Gul Mehboob Ahmed zaheer Ullah Khan Bilal Khan Mazhar Iqbal Hazara Agriculture Research Station Abbottabad Pakistan

Field studies were conducted at Hazara Agriculture Research Station, Abbottabad to evaluate thirteen AVRDC lines along with one commercial check (Roma) for potential of fruit yield against septoria leaf spot during summer season 2014. The disease established itself by natural infection and disease severity was estimated with the help of 0 - 5 disease rating scale after 15 days interval from the onset of symptoms. The lines showed significant difference in % septoria leaf spot infection. The disease severity % increased up to 100% in line AVTO1314 whereas the lowest % severity was recorded in AVTO1173 which showed the highest yield (468.1 g) with average fruit weight 122.22 g while the significantly lowest mean yield/plant (35.05 g) was calculated in line AVTO1314 with fruit weight 47.92 g. It was concluded that the line AVTO1173 could be useful in genetic programs for incorporating resistant genes in local tomato germplasm against septoria leaf spot disease.

关键词： Tomato Septoria Leaf Spot Disease Severity Fruit Yield

Statistical Analysis of Network Based Issues and Their Impact on Social Computing Practices in Pakistan

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Journal of Computer and Communications 2016年第13期4卷 23-39页

作者： Zahoor Hussain Zulﬁqar Ali Bhutto Gulab Rai Majid Hussain Kashif zaheer Institute of Information and Communication Technology University of Sindh Jamshoro Pakistan Education & Literacy Department Government of Sindh Karachi Pakistan Bahria University Karachi Campus Pakistan Department of Computer Science Karachi University Karachi Pakistan

Social computing and online groups have accompanied in a new age of the network, where information, networking and communication technologies are enabling systematized human efforts in primarily innovative ways. The social network communities working on various social network domains face different hurdles, including various new research studies and challenges in social computing. The researcher should try to expand the scope and establish new ideas and methods even from other disciplines to address the various challenges. This idea has diverse academic association, social links and technical characteristics. Thus it offers an ultimate opportunity for researchers to find out the issues in social computing and provide innovative solutions for conveying the information between social online groups on network computing. In this research paper we investigate the different issues in social media like users’ privacy and security, network reliabilities, and desire data availability on these social media, users’ awareness about the social networks and problems faced by academic domains. A huge number of users operated the social networks for retrieving and disseminating their real time and offline information to various places. The information may be transmitted on local networks or may be on global networks. The main concerns of users on social media are secure and fast communication channels. Facebook and YouTube both claimed for efficient security mechanism and fast communication channels for multimedia data. In this research a survey has been conducted in the most populated cities where a large number of Facebook and YouTube users have been found. During the survey several regular users indicate the certain potential issues continuously occurred on these social web sites interfaces, for example unwanted advertisement, fake IDS, uncensored videos and unknown friend request which cause the poor speed of channel communication, poor uploading and downloading data speed, cha

关键词： Computer Networks Categories of Social Computing Application Facebook and YouTube Potential Issues Statistical Analysis

Silver Nanoparticles: Green Route, Stability and Effect of Additives

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Journal of Biomaterials and Nanobiotechnology 2011年第4期2卷 390-399页

作者： zaheer Khan Javed Ijaz Hussain Sunil Kumar Athar Adil Hashmi Maqsood Ahmad Malik 不详

Colloidal silver nanoparticles were prepared by reducing silver nitrate with oxalic acid in presence of cetyltrimethylammonium bromide (CTAB). The synthesized silver particles show an intense surface plasmon band in the visible region. The work reported in this paper describes the effect of concentration of various additives (NaCl, NaBr, NaNO3, Na2SO4 and NaH2PO4) and ammonia on the growth and stability of Ag-nanoparticles. In all the cases the rate decreases as the [electrolytes] or [ammonia] increases. The nature, polarizability and coordinating ability of the anions play vital roles for nucleus formation and the growth process, which subsequently form different size particles. Transmission electron microscopy, selected areas electron diffraction, and UV-visible spectroscopy have been employed to characterize Ag-nanoparticles. The effect of the following variables on the particle size and size distribution was investigated: the [oxalic acid], [CTAB] and [Ag+].The nanoparticles are stable in NaNO3 and NaH2PO4 solutions;but NaCl, NaBr and Na2SO4 causes their aggregation.

关键词： Silver Nanoparticles Stability Oxalic Acid Additives Ammonia