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A BFSK and OOK IF demodulation circuit with 2.8 μs settling time and re-configurable image rejection functions for mics/BCC applications

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Journal of Semiconductors 2018年第7期39卷 104-109页

作者： Tongqiang Gao Zhenxiong Chen Siqi Zhao Haigang Yang Xinxia Cai Institute of Electronics Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

A BFSK and OOK IF base-band circuit is provided to implement the low-IF RF receivers for a dualband mics/BCC network controller. In order to transfer the massive vital data immediately, the IF circuit is comprised of the fast-settling feed-forward programmable gain amplifier（PGA）, a Gm-C complex filter, the fixed gain amplifier（FGA） and a 4-input ＂quadratic sum＂ demodulator. A novel auto-switched coarse gain-setting method is adopted in the PGA to enhance the reaction speed and narrow the output signal range. Also the PGA does not suffer the same stability constraint as open-loop topologies. The complex filter fulfills the function of image rejection,in which the center frequency and bandwidth can be adjusted individually. The FGA is used to ameliorate the linearity and the ＇quadratic sum＇ demodulator can reduce the overall power consumption. The designed IF circuit is fabricated with SMIC 0.18 μm CMOS process. The chip area is about 5.36 mm^2. Measurement results are given to verify the design goals.

关键词： low-IF receiver VGA complex filter mics BCC

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Wireless Engineering and Technology 2011年第2期2卷 107-111页

作者： Gopalakrishnan Srivatsun Sundaresan Subha Rani Gangadaran Saisundara Krishnan 不详

Low profile antenna in communication is a new methodology. Fractal geometry is a methodology through which size reduction is achieved. A Self-similar fractal antenna using multicantor technique is proposed and experimentally studied. Space-filling cantors and self-similarity properties of fractal geometry have been adopted in the proposed antenna to miniaturize the size of antenna. The antenna is designed in such a way to operate at mics band (Medical Implant communication Service) for wireless telemedicine application. The prototype antenna exhibits wideband characteristics and provides a good agreement of return loss (S11). Experimental return loss has been compared with that which is obtained using method of moments. The objective of using self-similar concept in antenna makes it flexible in terms of controlling the resonance and bandwidth. In this paper, the Self-similar property of fractal geometry is examined by maintaining return loss (S11) more than –30 dB approximately in all the iterations (n) and the prototype antenna has return loss greater than –10 dB and exhibits wideband characteristics.

关键词： Fractal Antenna Multicantor Self-Similar Antenna mics ISM Wideband Return Loss Wireless

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微型机互连及通讯系统(mics)

现代防御技术 1978年第5期 51-55页

作者：王风英

一般的计算机通讯网络常常严重地受到数据流阻塞的限制。进行必要的数据交换工作时要依靠大规模主计算机来控制它们的操作,编排次序和决定优先权。当较多的通讯终端设备增加到网络上时,主计算机需要使用控制功能,挤掉了一部分“生产性... 详细信息

一般的计算机通讯网络常常严重地受到数据流阻塞的限制。进行必要的数据交换工作时要依靠大规模主计算机来控制它们的操作,编排次序和决定优先权。当较多的通讯终端设备增加到网络上时,主计算机需要使用控制功能,挤掉了一部分“生产性”处理功能,从而导致了应用处理能力的减小和终端响应时间能力的显著减小。

关键词：通讯系统所有 mics 可编程序通道口微处理机数据总线存贮器存储器

纳米硼对Al/CuFe_(2)O_(4)@NC复合物点火和燃烧反应特性的影响

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火炸药学报 2023年第8期46卷 696-706,I0002页

作者：王为民贾睿张笑笑于佳杨航陈苏杭蒿银伟徐抗震赵凤起黎明化工研究设计院有限责任公司河南洛阳471000 西北大学化工学院陕西西安710069 西安近代化学研究所含能材料全国重点实验室陕西西安710065

为实现纳米铝热剂复合物反应活性的调节,采用静电喷雾技术制备了一系列不同Al/B摩尔比的Al/B/CuFe_(2)O_(4)@NC复合物,并通过XRD、FT-IR、SEM、DSC、激光点火和燃烧实验对复合物的相组成、结构和铝热反应特性进行系统表征分析。DSC结果... 详细信息

为实现纳米铝热剂复合物反应活性的调节,采用静电喷雾技术制备了一系列不同Al/B摩尔比的Al/B/CuFe_(2)O_(4)@NC复合物,并通过XRD、FT-IR、SEM、DSC、激光点火和燃烧实验对复合物的相组成、结构和铝热反应特性进行系统表征分析。DSC结果表明,纳米B有益于增加复合物的热释放能和提高其热稳定性,Al/B摩尔比为5/5工况下的热释放能由1138.5增至1426.9J/g,铝热反应温度随B含量的增加而提高。点火和燃烧实验发现,静电喷雾能显著增强复合物的反应活性,使其点火延迟由16ms降至10ms,燃速由3.34增至6.01cm/s;通过改变Al/B摩尔比,复合物的燃速、燃烧室压力增速和静电火花感度分别在6.01~36.36cm/s、0.05~0.17MPa/ms和61.25~11.25mJ之间可调,而当Al/B摩尔比小于5/5时,其点火和燃烧困难,表明B粉是调节复合物活性的有效添加剂。

关键词：物理化学亚稳态混合复合物 mics 静电喷雾纳米铝热剂激光点火燃烧反应

Religion and “Zero-Dose” Vaccination Status in Children Aged 12 to 23 Months in Benin and Togo: “Evidence of Demographic and Health Survey and Multiple Indicator Cluster Surveys”

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Open Journal of Epidemiology 2023年第4期13卷 306-327页

作者： Nyulelen Toyi Mangbassim Alphonse Kpozehouen Jacques Zinsou Saizonou Nicolas Gaffan Aissata Ba Sidibe Marie Therese Guigui Yaovi Temfan Toke Dadja Essoya Landoh Assima-Essodom Kalao Department of Epidemiology and Biostatistics Regional Institute of Public Health of Ouidah University of Abomey-Calavi Ouidah Benin Health Policy and Systems Department Regional Institute of Public Health of Ouidah University of Abomey-Calavi Ouidah Benin UNICEF Country Office of Togo Lome Togo World Health Organization Country Office of Togo Lome Togo Ministry of Health Public Hygiene and Universal Access to Care Lome Togo

Introduction: The relationship between religion and health has been a topic of interest in the past, and in recent years it has become increasingly visible in the social, behavioural, and health sciences. This work aims to study the influence of religion on the “zero-dose” vaccination status of children aged 12 - 23 months in Benin and Togo. Methods: This was a cross-sectional study which consisted in carrying out secondary analyzes using the databases of the most recent editions of the Demographic and Health Surveys in Benin and the Multiple Indicator Cluster Surveys (mics) in Togo. We extracted data concerning the vaccination status (“1 = zero-dose”, “0 = vaccinated”) of the children, the religious affiliation of the head of the household or the mother and other variables related to the child, the mother, the household and the environment. By means of a logistic regression, the adjusted effect of the religious affiliation of the head of the household or of the mother on the vaccination status at “zero-dose” was determined. Results: A total of 2430 and 933 children were respectively included in the study on behalf of Benin and Togo. The prevalence of “zero-dose” vaccination status in children aged 12 - 23 months was 33.91% (95% CI = 31.67 - 36.23) in Benin and this prevalence was 26.88% (95% CI = 23.50 - 30.55) in Togo. In Benin, there is no evidence in favour of the influence of the religious affiliation of the mother on the “zero-dose” vaccination status of children. In Togo, children living in households whose head was Muslim (ORa = 3.44;95% CI = 1.29 - 9.13) were more likely to be “zero-dose” than those coming from households run by individuals with no religious beliefs. Conclusion: Further research is needed to understand the basis for the excess risk of “zero-dose” vaccination status in children that appears to be associated with the Muslim religion.

关键词： Vaccination “Zero-Dose” Children Religion Evidence DHS mics Benin Togo

Antituberculosis and cytotoxic activities of triorganotin(Ⅳ) complexes

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Chinese Chemical Letters 2012年第6期23卷 731-735页

作者： Hidayat Hussain NaziaBibi Ahmed Al-Harrasi Salman Siddiqi Shahana U. Kazmi Ying Zhang Amin Badshah Department of Chemisty University of Paderborn 33098 Paderborn Germany Department of Biological Siences and Chemistry College of Arts and Sciences University of Nizwa Oman Immnology and Infectious Disease Research Laboratory Department of Microbiology University of＂ Karachi Pakistan Department of Molecular Muclvbiology and Immunology Bloomberg School of Public Health Johns Hopkins University Baltimore MD 21205 USA Becton Dickinson Diagnostic Systems Sparks MD 21152 USA Department of Chemistry Quaid-e-Azam University lslamabad 45320 Pakistan

Five triorganotin（IV）（1-5） complexes of cinnamic acid, （Z）-2-acetamido-3-phenylacrylic acid, 3-methylbut-2-enoic acid, and 2,2-diphenylacetic acid have been synthesized and characterized by IH-13C-119Sn NMR, UV, and IR. The spectroscopic investigation demonstrated that the carboxylate group acts as a monodentate ligand in triorganotin（IV） compounds. Five triorganotin（IV） complexes were screened against the log phase culture of Mycobacterium tuberculosis H37Rv by colorimetric method using XTT dye as growth indicator. The mics were found to he 0.08 and 1.25μg/mL.

关键词： Triorganotin(IV) complexes Antituberculosis activity mics Cytotoxicity

Antibiotic Resistance of Probiotic Strains of Lactic Acid Bacteria Isolated from Marketed Foods and Drugs

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Biomedical and Environmental Sciences 2009年第5期22卷 401-412页

作者： CHANG LIU, ZHUO-YANG ZHANG, KE DONG, JIAN-PING YUAN, AND XIAO-KUI GUO P1 P Department of Medical Microbiology and Parasitology, Institutes of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China Department of Medical Microbiology and Parasitology Institutes of Medical Sciences Shanghai Jiao Tong University School of Medicine Shanghai 200025 China

Objective To identify the antimicrobial resistance of commercial lactic acid bacteria present in microbial foods and drug additives by analyzing their isolated strains used for fermentation and probiotics. Methods Antimicrobial susceptibility of 41 screened isolates was tested with disc diffusion and E-test methods after species-level identification. Resistant strains were selected and examined for the presence of resistance genes by PCR. Results Distribution of resistance was found in different species. All isolates were susceptible to chloramphenicol, tetracycline, ampicillin, amoxicillin/clavulanic acid, cephalothin, and imipenem. In addition, isolates resistant to vancomycin, rifampicin, streptomycin, bacitracin, and erythromycin were detected, although the incidence of resistance to these antibiotics was relatively low. In contrast, most strains were resistant to ciprofloxacin, amikacin, trimethoprim/sulphamethoxazole, and gentamycin. The genes msrC, vanX, and dfrA were detected in strains of Enterococcus faecium, Lactobacillus plantarum, Streptococcus thermophilus, and Lactococcus lactis. Conclusion Antibiotic resistance is present in different species of probiotic strains, which poses a threat to food safety. Evaluation of the safety of lactic acid bacteria for human consumption should be guided by established criteria, guidelines and regulations.

关键词： Disc diffusion E-test mics vanX msrC dfrA

RDX@Al@PTFE复合材料制备及性能研究

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RDX@Al@PTFE复合材料制备及性能研究

作者：宋文魁西南科技大学

学位级别：硕士

现代武器系统和含能材料的发展主题一直离不开更高的能量水平和优异的燃烧性能。环三亚甲基三硝胺(RDX)、环四亚甲基四硝胺(HMX)、六硝基六氮杂异伍兹烷(CL-20)等单质含能材料与亚稳态分子间复合物材料(mics)集成为复合含能材料是提高... 详细信息

现代武器系统和含能材料的发展主题一直离不开更高的能量水平和优异的燃烧性能。环三亚甲基三硝胺(RDX)、环四亚甲基四硝胺(HMX)、六硝基六氮杂异伍兹烷(CL-20)等单质含能材料与亚稳态分子间复合物材料(mics)集成为复合含能材料是提高整体能量系统性能的补充策略。本论文通过设计和调整微观结构,利用RDX、聚多巴胺(PDA)涂层和聚四氟乙烯(PTFE)/铝粉通过超声合成技术构建核壳结构复合材料。由于核壳结构特征,实现了组分之间的紧密接触,保持组分自身性质实现了多种功能的结合以及复合材料性能的改善。具体研究内容如下:(1)通过对n-CuO/Al、n-FeO/Al、μ-FeO/Al、n-PTFE/Al和μ-PTFE/Al的热分解性能和燃烧过程进行分析。不同mics材料的热分解结果表明:n-FeO作为氧化剂拥有比n-Cu O更高的放热量以及更低的放热反应峰。聚四氟乙烯作为氧化剂在放热量上远大于两组金属氧化物,n-PTFE与Al反应放热量达到5511 J/g远大于n-FeO的1627 J/g。开放式燃烧试验结果表明,聚四氟乙烯与铝粉可以稳定传播火焰,并生成气体产物。(2)通过聚合物包覆RDX作为内层壳,设计了制备核壳结构材料的方法。聚酰胺甲酸乙酯(Estane)和聚多巴胺修饰RDX,分析了聚合物与RDX之间的相容性和对RDX微观形貌的影响。超声合成法制备了E-RDX@FeO/Al、E-RDX@PTFE/Al和P-RDX@PTFE/Al三种复合材料,通过与物理混合样品的对比燃烧实验,显示了Al-F体系核壳结构材料有着远快于Al-Fe体系的质量燃烧速率。结合SEM测试解释了E-RDX@PTFE/Al和P-RDX@PTFE/Al两组样品燃烧现象相似的原因。(3)通过调节多巴胺溶液浓度,以及反应时间,得到了三种RDX@PDA材料,通过超声合成技术获得对应的复合材料。SEM测试结果证明,利用低浓度多巴胺溶液在含能晶体表面形成均匀的涂层外壳,有效减少了PDA的聚合以及RDX之间的聚集,提高了样品分散性。SEM、XRD、FT-IR和XPS测试结果可以推断核壳结构复合材料的制备。DSC测试,发现在低升温速率下各组分的主要反应相对独立,核壳结构材料的放热量达到物理混合样品的2.9倍,并且Al-F反应得到了催化。燃烧实验结果表明,由于结构的优越性以及组分之间的功能互补,P-RDX@PTFE/Al展现出最佳的燃烧性能,燃烧稳定,火焰集中,燃烧速度快。摩擦和撞击感度测试表明了P-RDX@PTFE/Al在拥有出色的放热性能和燃烧性能以外,对机械刺激的敏感性降低,安全性得到了提高。综上所述,本文设计和制备了RDX@PDA@PTFE/Al纳米复合含能材料。PTFE/Al提高了复合材料的能量密度,PTFE作为外层壳发挥了缓冲和润滑的作用,降低了对机械刺激的敏感性;通过PDA涂层的强界面性能,确保了组分之间的紧密接触,降低了传质和传热距离,RDX与PTFE/Al之间的燃烧性能互补,促进了以对流为主导的火焰传播。因此,本文的研究结果为复合含能材料提高反应速率和能量输出效率提供了一种可行策略。

关键词：纳米复合含能材料聚多巴胺核壳结构 mics 协同效应

经食道超声心动图在微创心脏手术中的应用进展

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中国微创外科杂志 2023年第10期23卷 759-763页

作者：刘爽爽(综述) 宋亚男李民(审校) 北京大学第三医院麻醉科北京100191

与胸骨正中切开的传统心脏直视手术相比,微创心脏手术(minimally invasive cardiac surgery,mics)可以通过相对较小的切口(最大12.7 cm)进入胸腔进行手术。由于切口小、出血少、创伤应激小、术后疼痛感程度低、恢复快、远期效果良好等优... 详细信息

与胸骨正中切开的传统心脏直视手术相比,微创心脏手术(minimally invasive cardiac surgery,mics)可以通过相对较小的切口(最大12.7 cm)进入胸腔进行手术。由于切口小、出血少、创伤应激小、术后疼痛感程度低、恢复快、远期效果良好等优点,目前mics已越来越多地应用于临床[1~6]。

关键词：微创心脏手术经食道超声心动图心脏直视手术创伤应激远期效果切口 mics 应用进展