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Journal of Iron and Steel Research(International) 2020年第4期27卷 433-439页

作者： Le Zhang Wei Wang M.babar Shahzad Yi-yin Shan Ke Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026AnhuiChina Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina

A 5-layer laminated metal composite composed of ultrahigh-strength maraging steel and ductile 316L stainless steel was fabricated by hot pressing in vacuum and post-heat *** characterization on hierarchical structure of the composite before and after heat treatment was made by optical microscopy,scanning electron microscopy and electron back-scattered diffraction technique,***,the difference of mechanical performance on both sides of the interface was characterized by nano-hardness *** tensile test showed that superior interfacial bonding was achieved due to the micro-‘bite’structure between the two steels without obvious defects or oxides at the interface and with coordinated deformation of the two ***,a laminated metal composite consisting of two different constituents with extreme difference in strength can be well fabricated.

关键词： Maraging steel Austenitic stainless steel Laminated metal composite Hierarchical structure Interfacial

Enhancement of gut permeation of amoxicillin with Nigella sativa seed extract and its phytochemical screening

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Chinese Journal of Natural Medicines 2018年第2期16卷 125-130页

作者： babar Ali Mohammad Ali Saima Amin Showkat R.Mir College of Pharmacy and Dentistry Buraydah Colleges Phytopharmaceuticals Research Lab Department of Pharmacognosy and Phytochemistry School of Pharmaceutical Education and Research (Formerly Faculty of Pharmacy) Jamia Hamdard

The seeds of Nigella sativa Linn.(Ranunculaceae), commonly known as Black cumin, are predominantly used as carminative, antispasmodic, and stimulant. The main objective of the present study was to evaluate the effect of N. sativa seed extract on the permeation of co-infused amoxicillin across the gut wall. The methanolic extract of N. sativa improved intestinal permeability of amoxicillin in in-vitro experiments in a dose-dependent manner. Two new glycosides, decanyl nigelloic acid diglucoside [n-decanyl-3-aldehydic-4-methoxy-5-hydroxy benzoate-5-β-D-glucofuranosyl(2→1)-β-D-glucopyranosyl-(2→1)-β-D-glucopyranoside]] and nigelabdienoyl triglucoside [homo-labd-5, 9(11)-dien-16-onyl-β-D-glucopyranosyl(2→1)-β-D-glucopyranosyl(2→1)-β-D-glucopyranoside], along with seven known fatty acid glycerides/esters, were isolated from the gut permeation enhancing extract. The structures of these new glycosides were elucidated by detailed spectroscopic analyses.

关键词： Nigella sativa Everted rat sac Homolabdane Amoxicillin Bioavailability

Hot Deformation Behavior of an Ultra-High-Strength Fe–Ni–Co-Based Maraging Steel

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Acta Metallurgica Sinica(English Letters) 2019年第9期32卷 1161-1172页

作者： Le Zhang Wei Wang M. babar Shahzad Yi-Yin Shan Ke Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Hot processing behavior of an ultra-high-strength Fe–Ni–Co-based maraging steel was studied in temperature range of 900–1200℃and strain rate range of 0.001–10 s^-*** processing parameters and optimum hot working window were characterized via flow stress analysis,constitutive equation construction,hot processing map calculation and microstructure evolution,*** strain value for dynamic recrystallization was determined through theoretical mathematical differential method:the inflection point ofθ–σand-αθ/ασ-σ*** was found that the flow stress increased with the decrease in deformation temperature and increase in the strain *** power dissipation maps in the strain range of 0.1–0.6 were entirely similar with the tendency of contour lines which implied that strain had no strong effect on the dissipation ***,the instability maps showed obvious strain sensitivity with increasing strain,which was ascribed to the flow localization and *** optimized hot processing window of the experimental steel was obtained as 1100–1200℃/0.001–1 s^-1 and 1000–1100℃/0.001–0.1 s^-1,with the efficiency range of 20–40%.Owing to high Mo content in the experimental steel,high dynamic activation energy,Q=439.311 kJ mol^-1,was achieved,indicating that dynamic recrystallization was difficult to occur in the hot deformation process,which was proved via microstructure analysis under different hot deformation conditions.

关键词： Maraging steel Hot working Dynamic recrystallization Constitutive equation Hot processing map

Robinia pseudoacacia leaves improve soil physical and chemical properties

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Journal of Arid Land 2010年第4期2卷 266-271页

作者： babar KHAN Abdukadir Ablimit Rashed MAHMOOD Muhammad QASIM World Wide Fund for Nature Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences COMSATS Institute of Information Technology

The role of the leaves of Robinia pseudoacacia L., which is widely distributed in the arid lands, on improving soil physical and chemical properties was analyzed at various incubation periods. The incubated soils added with 0, 25, 50 and 75 g Robinia pseudoacacia leaves were tested after consecutive incubation intervals of 6, 8 and 10 months and the different soil parameters were measured. The results showed the increases in organic matter (OM), extractable K, cation exchange capacity (CEC), aggregate stability and water holding capacity, but the decreases in pH value and bulk density after 6 months’ incubation. The gradual decrease in change rates of soil properties indicated less microbial population and organic residual mineralization under acidic conditions, which were resulted from fast decomposition of leaves after the first 6 months incubation. The increases in soil organic matter content, extractable K, CEC, aggregate stability and water holding capacity and the decreases in soil pH and bulk density provide favorable conditions for crop’s growth.

关键词： soil physical and chemical properties Robinia pseudoacacia Gilgit-Baltistan

Ultra-thin Laminated Metal Composites with Ultra-high Strength and Excellent Soft Magnetic Properties

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Acta Metallurgica Sinica(English Letters) 2020年第3期33卷 385-390页

作者： Le Zhang Wei Wang Xiaofei Xiao M.babar Shahzad Yiyin Shan Ke Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Structural metallic materials with excellent functional performance and lightweight features have always been the goal of material scientists’ *** this work,laminated metal composites of different thicknesses(less than 0.4 mm) composed of structural materials with great differences in deformation ability were successfully fabricated via a novel processing ***-high strength and excellent soft magnetic properties were combined perfectly in the ultra-thin and super-light laminated metal composite strips due to unique structural design and essential attributes of the initial *** results emphasize the significant potential application value of the ultra-thin laminated metal composites in the field of structural and functional integration.

关键词： Laminated metal composites Ultra-high strength Ultra-thin Soft magnetic property Maraging steel

Hot deformation behavior of Cu-bearing antibacterial titanium alloy

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Journal of Materials Science & Technology 2018年第10期34卷 1867-1875页

作者： Zheng Ma Ling Ren M.babar Shahzad Rui Liu Ying Zhao Ke Yang Institute of Metal Research Chinese Academy of Sciences Center for Human Tissues and Organs Degeneration Shenzhen Institute of Advanced Technology Chinese Academy of Science

We investigated the deformation behavior of a new biomedical Cu-bearing titanium alloy （Ti-645 （Ti-6.06AI-3.75V-4.85Cu, in wt%）） to optimize its microstructure control and the hot-working process. The results showed that true stress-true strain curve ofti-645 alloy was susceptible to both deformation tem-perature and strain rate. The microstructure of Ti-645 alloy was significantly changed from equiaxed grain to acicular one with the deformation temperature while a notable decrease in grain size was recorded as well. Dynamic recovery （DRV） and dynamic recrystallization （DRX） obviously existed during the thermal compression of Ti-645 alloy. The apparent activation energies in （α ＋ β） phase and β single phase regions were calculated to be 495.21 kJ mo1^-1 and 195.69 kJ mo1^-1, respectively. The processing map showed that the alloy had a large hot-working region whereas the optimum window occurred in the strain rate range of 0.001-0.1 s-1, and temperature range of 900-960℃ and 1000-1050℃. The obtained results could provide a technological basis for the design of hot working procedure of Ti-645 alloy to optimize the material design and widen the ootential application of Ti-645 alloy in clinic.

关键词： cu-bearing titanium alloy Constitutive equation Thermal deformation Microstructure Processing map

Range extension of four highland agamid lizards in Shimshal Pamir,Pakistan

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Journal of Arid Land 2012年第1期4卷 77-84页

作者： babar KHAN Waseem AHMED Abdukadir Ablimit Shamim FAKHRI Hassan ALI Pakistan Wildlife Foundation Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences World Wide Fund for Nature Pakistan Zoological Survey Department

As part of the Sino-Pak trans-boundary cooperation for conservation and sustainable development in Pamir border region, World Wild Fund （WWF）-Pakistan conducted a preliminary social, economic and ecological survey in the ShimshaI-Pamir Lakes area in July 2009. The purpose of the study was to explore potentials and opportunities for future collaborative conservation of some species, habitats and high altitude ecosystems in the border region between China and Pakistan. The two-week herpetological study in the Shimshal Pamir area of Khunjerab National Park （KNP） along Pakistan-China border was an integral part of the survey, conducted exclu- sively to document reptilian fauna with a special emphasis on investigating their occurrence, distribution and status in the study area. Field investigations were performed during daytime when it was hot enough and reptiles were active, basking or feeding. A total of 15 specimens belonging to four species of the Agamidae family were captured by striking stones and beating bushes with sticks. Collected specimens were preserved using 10% formalin solution, tagged with field information and stored in Zoological Survey Department, Karachi for future reference. Laboratory investigations were carried out for pholidosic counts and morphometric measurements. A detailed review of relevant literature, habitat characteristics and laboratory investigations revealed the occurrence of Laudakia himalayana, L. pakistanica, L. tuberculata and L. badakhshana at 4,082 m, 4,172 m, 4,005 m and 4,240 m asl, respectively, which are much higher altitudes as compared to the previously reported heights of 3,353 m, 3,200 m, 2,500 m and 2,400 m asl. The terrain offers a variety of ecological barriers, in the form of fast and freezing running waters and massive glaciers with peculiar harsh climatic conditions prevailing for nine months of the year, which restricts species migration and thus increases endemism. Although one of the four species recorded from the

关键词： Laudakia himalayana L. pakistanica L. tuberculat L. badakhshana Agarnidae Gilgit-Baltistan Khunjerab National Park Pakistan

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基于高分2号卫星影像的兰州市城市绿地提取

基于高分2号卫星影像的兰州市城市绿地提取

作者：李特（babar Khan）兰州交通大学

学位级别：硕士

城市绿地（UGS）在维护城市生态平衡方面发挥着不可或缺的作用,随着卫星影像空间分辨率的不断提高,对城市绿地提取精度的要求也越来越高。深度学习算法已成为目标信息提取方法的首选,然而其存在样本数据集的构建工作量相对较大且整体提... 详细信息

城市绿地（UGS）在维护城市生态平衡方面发挥着不可或缺的作用,随着卫星影像空间分辨率的不断提高,对城市绿地提取精度的要求也越来越高。深度学习算法已成为目标信息提取方法的首选,然而其存在样本数据集的构建工作量相对较大且整体提取效率低等问题。如何充分利用绿地在影像中的光谱和空间特征,通过多特征集成处理,构建多特征集成专题信息提取模型一直是研究的重点和难点问题。为此,本文基于中国高分二号卫星影像,通过分析现有方法和影像特征,构建了新的城市绿地提取方法。本文主要工作为:（1）梳理研究了城市绿地提取方法。对常用的城市绿地提取方法进行分析,包括最大似然法、最小距离法、支持向量机法、面向对象法及光谱特征提取法。重点分析植被指数法,对比了各种不同植被指数,为后续研究提供技术支撑。（2）构建了一种新的多特征绿地提取模型。重复利用绿地在影像中的光谱反射特征,在植被指数、主成分分析、缨帽变化等方法的基础上,通过多特征集成和影像处理,构建了新的绿地提取模型,实现了较高精度的绿地自动提取。该方法不需要样本集,具有自动化程度高,计算效率快等优势。实验结果表明,本文方法解决了高分二号影像绿地信息高精度提取的问题,论文研究方法既为相关研究提供借鉴,同时可作为深度学习方法提取的前端处理,可进一步提高深度学习提取的精度和效率。

关键词：遥感图像处理高分2号影像城市绿地提取植被指数主成分变换

Analog Processing Based Vibration Measurement Technique Using Michelson Interferometer

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Photonic Sensors 2013年第2期3卷 137-143页

作者： babar HUSSAIN Mushtaq AHMED Ghazanfar HUSSAIN Muhammad SALEEM Muhammad NAWAZ National Institute of Lasers and Optronics 45650 Islamabad Pakistan

A Michelson interferometer based sensor, to monitor the displacement and vibration of a surface, is presented. The interference signals detected in quadrature are processed using analog electronics to find the direction of the motion of a vibrating surface in real-time. The complete instrumentation and signal processing are implemented for the interpretation of the amplitude as well as positive and negative excursion of the vibration cycles. This new technique is simpler as compared to the techniques commonly used in the interferometer based vibration sensors. Using this technique, we have measured mechanical vibrations having a magnitude of the order of nanometers and frequency in the range of 50 Hz to 500 Hz. By making small changes in the electronic circuit, the technique can be implemented for the extended range of the vibration frequencies and amplitude.

关键词：振动测量技术迈克尔逊干涉仪模拟处理振动传感器信号处理振动频率正交检测实时处理

Dissolution and repair of passive film on Cu-bearing 304L stainless steels immersed in H_2SO_4 solution

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Journal of Materials Science & Technology 2018年第11期34卷 2149-2159页

作者： Xinrui Zhang Jinlong Zhao Tong Xi M.babar Shahzad Chunguang Yang Ke Yang School of Materials Science and Engineering University of Science and Technology of China Institute of Metal Research Chinese Academy of Sciences

The antibacterial Cu-bearing 304 L stainless steel is a new kind of structural and functional integrated metal material. In this work, evolution behavior of passive film of different heat treated Cu-bearing 304 L stainless steel immersed in 0.5 M H2SO4 solution was investigated by using electrochemical measurements, atomic force microscopy（AFM） observation and X-ray photoelectron spectroscopy（XPS） *** results show that the solution and aging treated samples have the similar polarization behaviors. The passive film impedance experiences an initial decrease within 7 days followed by a subsequent increase,while the defect density of passive film presents the opposite trend. Meanwhile, the evolution of surface morphology and the estimated thickness of the passive film confirm that it experiences initial dissolution and follow-up repair. Furthermore, the Cr^3＋ content in passive film undergoes sequential reduction to increase, however the variation tendency of Cu^2＋ content is just opposite, indicating that the content variation of Cr and Cu in passive film reflects the competitive process of film dissolution and repair. In addition, compared with solution treated samples, aged samples have a bigger icorrvalue and the rougher passive film. This indicates that the passive film of solution treated steel is more compact and stable.

关键词： Cu-bearing stainless steel 304L-Cu Passive film