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Chinese Chemical Letters 2010年第6期21卷 720-724页

作者： Ishaat M.Khan ahmad naeem Afaq ahmad Department of Chemistry Faculty of Science Aligarh Muslim UniversityAligarh 202002UPIndia Department of chemistry Shibli National CollegeAzamgarh 276002UPIndia

The interactions of p-dimethylaminobenzaldehyde(p-DAB) and potassium hydrogen sulphate(PHS) in equimolar ratio with various concentration of diphenylamine(solid test material) have been investigated by capillary spot-tests technique in order to investigate the effect of temperature and volume of material in *** formation of the colored boundary in the capillary is taken for the detection of organic compounds by spot-tests at different temperature and volume of solid test material.

关键词： p-DAB Capillary spot-tests Solid material Potassium hydrogen sulphate

Enhanced biological nutrient removal by the alliance of a heterotrophic nitrifying strain with a nitrogen removing ecosystem

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Journal of Environmental Sciences 2008年第2期20卷 216-223页

作者： naeem ud din ahmad XU Haiying CHEN Liping LIU Zhipei LIU Shuangjiang State Key Laboratory of Microbial Resources Institute of Microbiology Chinese Academy of Sciences Beijing 100080 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

Nitrogen removal from synthetic wastewater was investigated in an airlift bioreactor （ALB）, augmented with a novel heterotrophic nitrifier Pseudonocardia ammonioxydans H9^T under organic carbon to nitrogen ratios （Corg/N） ranging from 0 to 12. Effect of the inoculated strain was also determined on the settling properties and the removal of chemical oxygen demand （COD）. Two laboratory scale reactors were set up to achieve a stable nitrifying state under the same physicochemical conditions of hydraulic retention time （HRT）, temperature, pH and dissolved oxygen （DO）, and operated under the sequencing batch mode. The level of DO was kept at 0.5- 1.5 mg/L by periodic stirring and aeration. Each specific Corg/N ratio was continued for duration of 3 weeks. One of the reactors （BR2） was inoculated with P ammonioxydans H9^T periodically at the start of each Corg/N ratio. Sludge volumetric index （SVI） improved with the increasing Corg/N ratio, but no significant difference was detected between the two reactors. BR2 showed higher levels of nitrogen removal with the increasing heterotrophic conditions, and the ammonia removal reached to the level of 82%-88%, up to10% higher than that in the control reactor （BR1） at Corg/N ratios higher than 6; however, the ammonia removal level in experimental reactor was up to 8% lower than that in control reactor at Corg/N ratios lower than 2. The COD removal efficiency progressively increased with the increasing Corg/N ratios in both of the reactors. The COD removal percentage up to peak values of 88%-94% in BR2, up to 11% higher than that in BR1 at Corg/N ratio higher than 4. The peak values of ammonia and COD removal almost coincided with the highest number （18%-27% to total bacterial number） of the exogenous bacterium in the BR2, detected as colony forming units （CFU）. Furthermore, the removal of ammonia and COD in BR2 was closely related to the number of the inoculated strain with a coefficient index （R2） up to 0.82 and 0.85 for ammonia

关键词： air-lift bioreactor (ALB) bioaugrnentation Corg/N ratio COD and ammonia removal sequencing batch mode heterotrophic nitrifier Pseudonocardia ammonioxydans H9^T

V-Shaped Monopole Antenna with Chichena Itzia Inspired Defected Ground Structure for UWB Applications

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Computers, Materials & Continua 2020年第10期65卷 19-32页

作者： naeem ahmad Jan Saad Hassan Kiani Fazal Muhammad Daniyal Ali Sehrai Amjad Iqbal Muhammad Tufail Sunghwan Kim Department of Electrical Engineering Iqra National UniversityPeshawar25000Pakistan Department of Electrical Engineering City University of Science and Information TechnologyPeshawar25000Pakistan Department of Electrical Engineering Multimedia UniversityCyberjaya63100Malaysia Department of Mechatronics Engineering University of Engineering and TechnologyPeshawar25000Pakistan Department of Electrical Engineering University of UlsanUlsan44610Korea

Due to rapid growth in wireless communication technology,higher bandwidth requirement for advance telecommunication systems,capable of operating on two or higher bands with higher channel capacities and minimum distortion losses is *** this paper,a compact Ultra-Wideband(UWB)V-shaped monopole antenna is *** response is achieved by modifying the ground plane with Chichen Itzia inspired rectangular staircase *** proposed V-shaped is designed by incorporating a rectangle,and an inverted isosceles triangle using FR4 *** size of the antenna is 25 mm×26 mm×1.6 *** proposed V-shaped monopole antenna produces bandwidth response of 3 GHz Industrial,Scientific,and Medical(ISM),Worldwide Interoperability for Microwave Access(WiMAX),(IEEE 802.11/HIPERLAN band,5G sub 6 GHz)which with an additional square cut amplified the bandwidth response up to 8 GHz ranging from 3.1 GHz to 10.6 GHz attaining UWB defined by Federal Communications Commission(FCC)with a maximum gain of 3.83 *** antenna is designed in Ansys *** for key performance parameters of the antenna are *** measured results are in good agreement with the simulated *** to flat gain,uniform group delay,omni directional radiation pattern characteristics and well-matched impedance,the proposed antenna is suitable for WiMAX,ISM and heterogeneous wireless systems.

关键词： V-shape monopole gain staircase ultra-wideband omni-directional defected ground structure

Design of a Compact Monopole Antenna for UWB Applications

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Computers, Materials & Continua 2021年第1期66卷 35-44页

作者： naeem ahmad Jan Saad Hassan Kiani Daniyal Ali Sehrai Muhammad Rizwan Anjum Amjad Iqbal Mujeeb Abdullah Sunghwan Kim Department of Electrical Engineering Iqra National UniversityPeshawar25000Pakistan Department of Electrical Engineering City University of Science and Information TechnologyPeshawar25000Pakistan Department of Electronic Engineering The Islamia University of BahawalpurBahawalpur63100Pakistan Department of Electrical Engineering Multimedia UniversityCyberjaya63100Malaysia Department of Computer Science Bacha Khan UniversityCharsadda24420Pakistan School of Electrical Engineering University of UlsanUlsan44610Korea

In this paper,a low cost,highly efficient and low profile monopole antenna for ultra-wideband(UWB)applications is presented.A new inverted triangular-shape structure possessing meander lines is designed to achieve a wideband response and high *** design the proposed structure,three steps are utilized to achieve an UWB *** bandwidth of the proposed antenna is improved with changing meander lines parameters,miniaturization of the ground width and optimization of the feeding *** measured and simulated frequency band ranges from 3.2 to 12 GHz,while the radiation patterns are measured at 4,5.3,6 and 8 GHz frequency *** overall volume of the proposed antenna is 26×25×1.6 mm^(3);whereas the FR4 material is used as a substrate with a relative permittivity and loss tangent of 4.3 and 0.025,*** peak gain of 4 dB is achieved with a radiation efficiency of 80 to 98%for the entire *** modelling of proposed antenna is performed in ANSYS HFSS 13 software.A decent consistency between the simulated and measured results is accomplished which shows that the proposed antenna is a potential candidate for the UWB applications.

关键词： Ultra-wideband(UWB) meander lines monopole antenna high efficiency high gain ANSYS HFSS

Influence of P-enriched compost application on economics and P use efficiency of a maize–wheat rotation system

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The Crop Journal 2018年第6期6卷 651-658页

作者： Abdul Majeed Shahzada Munawar Mehdi Abid Niaz Abid Mahmood Ehsan-Ul-Haq naeem ahmad Shahid Javid Atif Mehmood Sugarcane Research Institute Faisalabad Ayub Agricultural Research InstitutePunjabPakistan Soil Fertility Research Institute LahoreAyub Agricultural Research InstitutePunjabPakistan Institute of Soil Chemistry and Environmental Sciences Ayub Agricultural Research InstitutePunjabPakistan Ayub Agricultural Research Institute PunjabPakistan Provincial Reference Fertilizer Testing Laboratory Raiwind LahorePunjabPakistan Key Laboratory of Clean Utilization Technology for Renewable Energy Ministry of AgricultureCollege of EngineeringChina Agricultural UniversityBeijing 100083China

Crop phosphorus(P) deficiency and poor utilization of added P is a major agricultural problem due to reduced solubility of soil P and rapid fixation or precipitation of applied P fertilizer in alkaline and calcareous soils. The effects of P-enriched compost and single superphosphate(SSP) fertilization on maize and wheat yields and P use efficiency in a maize–wheat rotation system were studied for three years. On a three-year average, grain yields of maize and wheat after application of P-enriched compost were increased by 18% and 24%, respectively, in comparison with sole addition of a recommended dose of SSP fertilizer. P-enriched compost addition to soil increased maize and wheat yields by 12% and 17%, respectively, compared to P fertilizer plus FYM incorporation. Soil available P concentration and P uptake were affected significantly by the addition of P-enriched compost. On average, increases in P recovery, use efficiency, and agronomic efficiency of 52%, 18%, and 43% were recorded in maize and increases of 50%, 23%, and 49% in wheat. P-enriched compost application yielded 30% and 32%higher economic returns in maize and wheat than SSP fertilization alone.

关键词： P-enriched compost Maize Wheat Farmyard manure P-uptake

Effect of different catalysts and growth temperature on the photoluminescence properties of zinc silicate nanostructures grown via vapor-liquid-solid method

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Chinese Physics B 2022年第5期31卷 657-665页

作者： Ghfoor Muhammad Imran Murtaza Rehan Abid naeem ahmad Department of Physics International Islamic UniversityIslamabad 44000Pakistan

We explore the photoluminescence properties of zinc silicate(Zn_(2)SiO_(4)) nanostructures synthesized by vapor-liquidsolid(VLS)mode of growth using three different catalysts(Sn,Ag,and Mn).Different catalysts significantly influence the growth rate which in turn has an impact on the structure and hence the photoluminescence of the prepared zinc silicate ***_(2)SiO_(4) has a wide bandgap of about 5.5 eV and in its pure form,it does not emit in visible region due to its inner shell electronic transitions between the 3 d5 energy ***,the incorporation of different catalysts(Sn,Ag and Mn)at different growth temperatures into the Zn_(2)SiO_(4) crystal growth kinetics provides wide visible spectral range of photoluminescence(PL)*** analysis shows broad multi-band spectrum in the visible region and distinct colors(red,yellow,green,blue,cyan and violet)are obtained depending on the crystalline structure of the prepared *** allowed transitions due to the effect of different catalysts on zinc silicate lattice offer a huge cross-section of absorption that generates strong *** correlation between the structural and optical properties of the synthesized nanostructures is discussed in *** synthesized photoluminescent nanostructures have potential applications in solidstate lighting and display devices.

关键词： nanostructures vapor-liquid-solid growth mode photoluminescence spectra fluorescence microscopy

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核电厂上充管热疲劳特性研究

核电厂上充管热疲劳特性研究

作者： naeem ahmad 华北电力大学(北京)

学位级别：硕士

核电厂的安全问题一直以来是困扰许多想要利用核能的消费者的主要问题。组件的疲劳失效不仅是一种重要的故障,并且对核电厂来说也是一个高危的安全隐患。核电厂的许多组件需要承受热应力,内部压力和热瞬态。这些组件一次次的承受热瞬态... 详细信息

核电厂的安全问题一直以来是困扰许多想要利用核能的消费者的主要问题。组件的疲劳失效不仅是一种重要的故障,并且对核电厂来说也是一个高危的安全隐患。核电厂的许多组件需要承受热应力,内部压力和热瞬态。这些组件一次次的承受热瞬态可能导致部件发生热疲劳现象。长期循环往复会使核电厂部件发生损坏。一些研究曾对弯管和三通管进行研究,但对化容系统中的上充管还未进行热疲劳的分析。上充管连接化容系统(RCV)和反应堆冷却剂系统(RCP)。为提高上充管的安全性,使用流固耦合(FSI)的方法对管道系统的热疲劳进行分析评估。管道的温度分布用ANSYS CFX软件计算得出。使用ANSYS瞬态结构分析,将温度分布放入管道系统的结构模型中来得出热应力。使用ANSYS利用这些应力进一步研究管道系统的疲劳特性。对CFD进行初始条件的设置;时间步长未1s,总时间为200s,取k-ω湍流模型。初步的实验结果表明热分层现象出现在上充管与RCP系统管道的连接处,因此热应力出现的位置在两管道连接处。所以使用CFD来分析较小的模型。分析确定了湍流的作用,其类似于结构的热负荷。结果显示,由于两管连接处的流体不对称,会产生绕流。使用有限元分析来映射结构中的温度变化。有限元分析表明最大热应力和最易发生热疲劳的位置在靠近主管道的环管处。发生热应力变化最大的位置在两管道连接处,靠近RCP管道出口方向的一侧管道。疲劳寿命最低处会出现在两管连接处的最大应力值处。这项研究能够快速的评估上充管的疲劳特性,为建立一种可以减小核电厂疲劳损害的方法提供有价值的信息。

关键词：流固耦合(FSI) 上充管热应力热疲劳

Expansion of human umbilical cord derived mesenchymal stem cells in regenerative medicine

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World Journal of Stem Cells 2024年第4期16卷 410-433页

作者： Shafiqa naeem Rajput Bushra Kiran naeem Anwar Ali Asmat Salim Irfan Khan Dr.Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological SciencesUniversity of KarachiKarachi 75270SindhPakistan Surgical Unit 4 Dr.Ruth KM Pfau Civil HospitalKarachi 74400Pakistan Department of Physiology University of KarachiKarachi 75270Pakistan Center for Regenerative Medicine and Stem Cells Research and Department of Ophthalmology and Visual SciencesThe Aga Khan UniversityKarachi 74800SindhPakistan

BACKGROUND Stem cells are undifferentiated cells that possess the potential for self-renewal with the capacity to differentiate into multiple *** humans,their limited numbers pose a challenge in fulfilling the necessary demands for the regeneration and repair of damaged tissues or *** suggested that mesenchymal stem cells(MSCs),necessary for repair and regeneration via transplantation,require doses ranging from 10 to 400 million ***,the limited expansion of MSCs restricts their therapeutic *** To optimize a novel protocol to achieve qualitative and quantitative expansion of MSCs to reach the targeted number of cells for cellular transplantation and minimize the limitations in stem cell therapy *** Human umbilical cord(hUC)tissue derived MSCs were obtained and *** cultured cells were subjected to the following evaluation pro-cedures:Immunophenotyping,immunocytochemical staining,trilineage differentiation,population doubling time and number,gene expression markers for proliferation,cell cycle progression,senescence-associatedβ-galactosidase assay,human telomerase reverse transcriptase(hTERT)expression,mycoplasma,cytomegalovirus and endotoxin *** Analysis of pluripotent gene markers Oct4,Sox2,and Nanog in recultured hUC-MSC revealed no significant *** immunophenotypic markers CD90,CD73,CD105,CD44,vimentin,CD29,Stro-1,and Lin28 were positively expressed by these recultured expanded MSCs,and were found negative for CD34,CD11b,CD19,CD45,and *** recultured hUC-MSC population continued to expand through passage *** gene expression of Pax6,BMP2,and TGFb1 showed no significant variation between recultured hUC-MSC ***,a significant increase(P<0.001)in the mitotic phase of the cell cycle was observed in recultured *** senescence markers(hTERT expression andβ-galactosidase activity)did not show any negative effect on recultured hUC-

关键词： Human umbilical cord Mesenchymal stem cells Expansion Cell proliferation In vitro expansion Senescence

气提式三重循环生物膜反应器处理制药废水中的甾体雌激素

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环境科学研究 2006年第4期19卷 56-60页

作者：崔成武纪树兰任海燕 naeem ud din ahmad 韩磊北京工业大学环境与能源工程学院北京100022 中国科学院微生物研究所北京100080

为验证气提式三重循环生物膜反应器处理甾体雌激素的效能，建立了一套SPE／HPLC／MS／MS分析方法，对反应器进、出水中的甾体雌激素——甾酮（E1），17β-雌二醇（E2），雌三醇（E3）以及17α-乙炔基雌二醇（EE2）进行检测．该方法的加... 详细信息

为验证气提式三重循环生物膜反应器处理甾体雌激素的效能，建立了一套SPE／HPLC／MS／MS分析方法，对反应器进、出水中的甾体雌激素——甾酮（E1），17β-雌二醇（E2），雌三醇（E3）以及17α-乙炔基雌二醇（EE2）进行检测．该方法的加标回收率为88％～103％，精密度为4％～9％．该方法对E1，E2，E3和EE2的进水定量限（LOQ）分别为0．7，0．8，0．9和0．5ng／L；对出水的定量限分别为2．0，1．0，2．0和1．0ng／***和氨氮容积负荷最高为7．5和1．6kg／（m^3·d），出水依然能够保持稳定．进水pH稳定在9．0～10．5，而反应器的pH一直稳定在9．0以下，体系对pH变化造成的冲击比较适应．同时，反应器内形成了稳定的NO2^- -N积累，CODCr和氨氮的去除率分别达到了70％和73％．

关键词：气提式三重循环生物膜反应器 SPE/HPLC/MS/MSW分析方法甾体雌激素短程硝化

气提式三重循环生物膜反应器用于制药废水的处理

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中国给水排水 2006年第5期22卷 80-83页

作者：任海燕纪树兰崔成武韩磊 naeem ud din ahmad 王道北京工业大学环境与能源工程学院北京100022 中国科学院微生物研究所北京100080

采用气提式三重循环生物膜反应器（TLABR）处理制药废水，稳定阶段对COD和NH4^＋-N的去除率分别为73％和70％。当温度为27～30℃、pH=8．5时，反应器内形成了稳定的NO2^--N积累。同时，考察了不同HRT下高效反应器的处理效果，探讨了pH... 详细信息

采用气提式三重循环生物膜反应器（TLABR）处理制药废水，稳定阶段对COD和NH4^＋-N的去除率分别为73％和70％。当温度为27～30℃、pH=8．5时，反应器内形成了稳定的NO2^--N积累。同时，考察了不同HRT下高效反应器的处理效果，探讨了pH对反应器内发生的短程硝化效果的影响以及亚硝化菌对游离氨浓度的适应性。结果表明：在HRT为3、6、9h下，对COD和氨氮的去除率分别为65．3％、73．9％、75．1％和48．9％、68．4％、72．8％；NO2^--N积累率分别为92．7％、76．2％、69．7％；反应器出水水质稳定，体现了高效性和抗冲击负荷能力。

关键词：制药废水气提式三重循环生物膜反应器甾体雌激素短程硝化