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101.
102.
A 25 Gbit/s clock and data recovery(CDR) circuit with 1:2 demultiplexer for 100 Gbit/s Ethernet(100 Gb E) optical interconnects has been designed and fabricated in Taiwan Semiconductor Manufacture Company(TSMC) 65 nm complementary metal-oxide-semiconductor(CMOS) technology. A novel quadrature voltage-controlled-oscillator(QVCO) structure adopts two pairs of transconductance cell and inverters to acquire rail-to-rail output swing. A half-rate bang-bang phase detector adopts four flip-flops array to sample the 25 Gbit/s input data and align the data phase, so the 25 Gbit/s data are retimed and demultiplexed into two paths 12.5 Gbit/s output data. Experimental results show that the recovered clock exhibits a peak-to-peak jitter of 7.39 ps and the recovered data presents a peak-to-peak jitter of 7.56 ps, in response to 312-1 pseudorandom bit sequence(PRBS) input. For 1.2 V voltage supply, the CDR circuit consumes 92 m W(excluding output buffers).  相似文献   
103.
104.
受限空间内天然气爆炸反应过程模拟分析   总被引:1,自引:0,他引:1  
为定量研究受限空间内天然气爆炸反应动力学特征,开展了3个方面的研究工作,①建立了基于激波管的天然气爆炸过程数值分析模型;②将天然气气相燃烧动力学反应分解为53种反应组分、325种基元反应,给出了朗金―雨贡尼关系式和正激波的压强比、密度比和温度比计算方法;③利用化学反应模拟软件CHEMKIN构建天然气燃烧过程机理文件,对激波诱导受限空间内天然气混气爆炸过程进行数值模拟,讨论了反应过程、初始压力和空间尺寸对天然气爆炸过程的影响,并绘制了天然气爆炸温度、压力变化特征曲线。结果表明:采用入射激波模拟混气引爆过程中体系温度会出现跳跃式上升随之向下扰动;混气被引爆后温度逐步提高,在温度达到峰值时压力随之提高;提高初始压力将缩短混气引爆时间,高的初始压力可以得到更为迅速的反应速度和更高的爆炸压力;空间尺寸对散热作用的影响高于其对活性基团消毁作用的影响,小尺寸空间条件下可以获得更迅速的爆炸升压速度。  相似文献   
105.
Objective: Establish an effective experimental strategy to determine the compatibility of rubber closures for drugs.

Significance: Various types of rubber closures with different compositions are available for drug packaging. Many additives of rubber closures can be released from rubber closures and may affect the quality of drugs and pose a risk to human health. In this study, we aimed to determine the relationship between cephalosporin structure, solution clarity, and rubber closure compatibility using volatile components profile of butyl rubber closures.

Methods: Two opposite polarity gas chromatography (GC) systems and GC-mass spectrometry (MS) were used to achieve rapid qualitative determination of the main volatile components in rubber closures. Simulated adsorption experiment was performed to investigate the adsorption of main volatile components in rubber closures by cephalosporins with different side chain structures, and to determine the effects of adsorption on solution clarity.

Results: A volatile components screening library of rubber closures was established and the structures of some volatile component were confirmed. The specific adsorption of the structure of cephalosporins on volatile components from rubber closures was studied.

Conclusion: Based on the results of this study, rubber closures with good compatibility for cephalosporins with different side chain structures can be selected rapidly. This experimental strategy not only facilitates the screening of suitable rubber closures more effectively, but also enables the quick determination of volatile components adsorbed by drugs.  相似文献   

106.
Shuai  Yuhong  Yao  Liming 《Water Resources Management》2021,35(12):4043-4065

Optimal water resource allocation can go some way to overcoming water deficiencies; however, its achievement is complex due to conflicting hierarchies and uncertainties, such as water availability (WA) and water demand (WD). This study develops a robust water withdrawal scheme for drought regions that can balance the trade-offs between the sub-areas and water use participants, ensure sustainable regional system development, and guarantee robust solutions for future uncertainties. A bi-level affinely adjustable robust counterpart (AARC) programming framework was developed in which the regional authority as the leader allocates water to the sub-areas to maximize the intra- and intergenerational equity, and the sub-areas as the followers allocate water to their respective water departments to maximize their economic benefits and minimize water shortages. A case study from Neijiang, China, is given to illustrate the applicability and feasibility of this framework. The novelty of this study is to propose a sustainable bi-level AARC regional water allocation framework which integrates intra- and inter-generational equity of regional water use and priority rules reflected by goal preference programming between water departments under uncertainties of WA and WD simultaneously in water deficient regions.

  相似文献   
107.
In this paper,polycrystalline samples of Bi_(1-x)Sm_xFeO~3(x=0,0.05,0.1,0.15) were successfully synthesized by sol-gel method.The effects of Sm concentration on the crystal structure,morphology,chemical states,magnetic properties and microwave absorption performance were studied by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),a vibrating sample magnetometer(VSM) and a Vector network analyzer(VNA),respectively.The results show that the rare earth Sm doping causes the crystal structure to change.When x≤0.1,Bi_(1-x)Sm_xFeO_3 is the distorted rhombohedral structure with space group R3 c.With the increase of Sm doping amount to x=0.15,the phase structure of Bi_(1-x)Sm_xFeO_3 changes from rhombohedral structure to cubic structure with the space group Pm3 m.The particle size decreases with the increase of the Sm doping amount.The analysis results show that Sm doping can effectively reduce the oxygen vacancies and significantly improve its magnetic properties.The results exhibit that moderately doped rare earth Sm element can effectively improve microwave absorption properties of Bi_(1-x)Sm_xFeO_3 powders.When Sm doping amount of x is 0.1,the Bi_(0.9)Sm_(0.1) FeO_3 compound has good microwave absorption performance,and the minimum reflection loss value of Bi_(0.9)Sm_(0.1)FeO_3 powder reaches about-32.9 dB at11.7 GHz,and its effective absorption bandwidth(RL -10 dB) is 2.6 GHz with the optimal matching thickness of 2.0 mm.  相似文献   
108.
针对国内某车桥制造企业采用无缝钢管生产大胀形率车桥时出现的胀形区域开裂问题,设计开发了适用于大胀形率车桥用钢,并进行了无缝钢管产品试制和使用评价.结果表明,采用设计开发钢种生产的车桥用无缝钢管,延伸率为28%~31%,-60℃的纵向冲击功达到80 J,产品具有良好的塑性和低温冲击韧性.经用户批量使用,采用设计钢种生产的无缝钢管在大胀形时未发生开裂现象.  相似文献   
109.
Poor strength, infection, leakage, long procedure times, and inflammation limit the efficacy of common tissue sealing devices in surgeries and trauma. Light-activated sealing is attractive for tissue sealing and repair, and can be facilitated by the generation of local heat following absorption of nonionizing laser energy by chromophores. Here, the inherent ability of biomaterials is exploited to absorb nonionizing, mid-infrared (midIR) light in order to engender rapid photothermal sealing and repair of soft tissue wounds. In this approach, the biomaterial simultaneously acts as a photothermal convertor as well as a biosealant, which dispenses the need for exogeneous light-absorbing nanoparticles or dyes. Biomechanical recovery, mathematical modeling, histopathology analyses, tissue strain mapping using digital imaging correlation, and visualization of the biosealant-tissue interface using hyperspectral imaging indicate superior performance of midIR sealing in live mice compared to conventional sutures and glue. The midIR-biosealant approach demonstrates rapid sealing of soft tissues, improves cosmesis, lowers potential for scarring, obviates safety concerns because of the nonionizing light used, and allows adoption of a wide diversity of biomaterials. Taken together, the studies demonstrate a novel advance both in biomaterials for surgical sealing along with the use of nonionizing midIR light, with high potential for clinical translation.  相似文献   
110.
The extensive research interests in environmental temperature can be linked to human productivity / performance as well as comfort and health; while the mechanisms of physiological indices responding to temperature variations remain incompletely understood. This study adopted a physiological sensory nerve conduction velocity (SCV) as a temperature‐sensitive biomarker to explore the thermoregulatory mechanisms of human responding to annual temperatures. The measurements of subjects’ SCV (over 600 samples) were conducted in a naturally ventilated environment over all four seasons. The results showed a positive correlation between SCV and annual temperatures and a Boltzmann model was adopted to depict the S‐shaped trend of SCV with operative temperatures from 5°C to 40°C. The SCV increased linearly with operative temperatures from 14.28°C to 20.5°C and responded sensitively for 10.19°C‐24.59°C, while tended to be stable beyond that. The subjects’ thermal sensations were linearly related to SCV, elaborating the relation between human physiological regulations and subjective thermal perception variations. The findings reveal the body SCV regulatory characteristics in different operative temperature intervals, thereby giving a deeper insight into human autonomic thermoregulation and benefiting for built environment designs, meantime minimizing the temperature‐invoked risks to human health and well‐being.  相似文献   
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