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991.
贾鹏  丁召  杨发顺 《现代电子技术》2013,(24):156-159,163
基于传统带隙基准的原理,通过优化电路结构,消除双极晶体管基极.发射极电压中的非线性项,设计了一种带2阶补偿的多输出带隙基准电压源。整个电路采用CSMC0.5μmCMOS工艺模型进行仿真。Spectre仿真结果表明,在-55~125℃的温度范围内,带隙基准电压源的温度系数为3.1ppm/℃,在5V电源电压下,输出基准电压为1.2994V;带隙基准电压源的电源抑制比在低频时为84.5dB;在5v电源电压下,可以同时输出0—5V多个基准电压。  相似文献   
992.
魏鹏  赵河明  张志 《山东电子》2013,(5):102-105
主要介绍了弹丸炮口测速方法数据隔离和采集系统,以FPGA为逻辑控制单元,搭载ADS8508为数据转换模块;系统完成12位精度数据转换,实现了炮口测速。介绍了该控制FPGA由硕至下模块化设计的具体实现方案.并给出其核心模块的状态跃迁图及时序仿真波形。  相似文献   
993.
The judicious design of 3D giant organic dye molecules to enable the formation of a porous photoactive layer on the surface of titania is one of the viable tactics to abate the adverse interfacial charge recombination in dye‐sensitized solar cells (DSCs) employing outer‐sphere redox couples. Here 2′,6′‐bis(octyloxy)‐biphenyl substituted dithieno[3,2‐b:2′,3′‐d]pyrrole segment is constructed and employed as the π‐linker of a high molar absorption coefficient organic push‐pull dye. With respect to its congener possessing the hexyl substituted dithieno[3,2‐b:2′,3′‐d]pyrrole linker, the new dye can self‐assemble on the surface of titania to afford a porous organic coating, which effectively slow down the kinetics of charge recombination of titania electrons with both outer‐sphere tris(1,10‐phenanthroline)cobalt(III) ions and photooxidized dye molecules, improving the cell photovoltage. In addition, the diminishments of charge recombination via modulating the microstructure of interfacial functional zone can also overcompensate the disadvantageous impact of reduced light‐harvesting and evoke an enhanced photocurrent output, bringing forth an efficiency improvement from 7.5% to 9.3% at the 100 mW cm?2, simulated AM1.5 conditions.  相似文献   
994.
目的:建赢稳定的重性抑郁血浆双向凝胶电泳技术体系。方法:从血浆蛋自质样品制备、等电聚焦和水化方式等方面对双向凝胶电泳分离技术进行优化。结果:建立了稳定的抑郁症血浆双向凝胶电泳图谱,达到了较好的血浆蛋白分离效果。结论:成功的血浆图谱构建,为进一步开展重性抑郁诊断和机制研究奠定基础。  相似文献   
995.
在接入网中,低成本、小尺寸的同轴结构封装10 Gb/s光接收组件起着非常重要的作用。在微波频段,封装器件引入的寄生参数已经成为制约其高频特性的主要因素之一。基于传输线理论,建立了包含芯片、金丝、管座的小信号等效电路模型。等效电路元件与实际封装器件有对应的关系。组件高频特性随元件参数值变化而变化。仿真结果表明金丝对其高频特性影响很严重。为了减小金丝电感,提出一种优化方案。并结合实际工艺条件,制作了样品,实验结果表明该样品的传输速率达到10 Gb/s,满足10 Gb/s光网络传输的要求。  相似文献   
996.
Patients with diabetes mellitus (DM) suffer from a high risk of fractures and poor bone healing ability. Surprisingly, no effective therapy is available to treat diabetic bone defect in clinic. Here, a 3D printed enzyme-functionalized scaffold with multiple bioactivities including osteogenesis, angiogenesis, and anti-inflammation in diabetic conditions is proposed. The as-prepared multifunctional scaffold is constituted with alginate, glucose oxidase (GOx), and catalase-assisted biomineralized calcium phosphate nanosheets (CaP@CAT NSs). The GOx inside scaffolds can alleviate the hyperglycemia environment by catalyzing glucose and oxygen into gluconic acid and hydrogen peroxide (H2O2). Both the generated H2O2 as well as the overproduced H2O2 in DM can be scavenged by CaP@CAT NSs, while the initiated hypoxic microenvironment stimulates neovascularization. Moreover, the incorporation of CaP@CAT NSs not only enhance the mechanical property of the scaffolds, but also facilitate bone regeneration by the degraded Ca2+ and PO43− ions. The remarkable in vitro and in vivo outcomes demonstrate that enzymes functionalized scaffolds can be an effective strategy for enhancing bone tissue regeneration in diabetic conditions, underpinning the potential of multifunctional scaffolds for diabetic bone regeneration.  相似文献   
997.
Public adoption of policies detailed on government websites is an important topic in the field of e-government research, and researchers have mainly focused on the key factors that influence initial adoption. However, there has been much less discussion on factors influencing the continued use of government websites. This study identifies and tests a theoretical model that predicts consumers’ intentions to continue using government portals, using a mixed methods approach based on Grounded Theory. To construct a theoretical framework of public interest in continued use of government information portals, we interviewed 56 respondents and coded the interview data. Next, we tested the resulting model using data collected from a questionnaire-based survey of 354 users. The Structural Equation Modeling (SEM) results indicate that continued use is influenced by psychological perception, user characteristics, service parameters of the government portals and the government’s idea. Of these, psychological perception was found to have the strongest effect. These findings enrich the theoretical system of e-government public adoption of intention and have important practical significance for the development of Chinese government portals.  相似文献   
998.
A key factor for successful design of bioactive complex, organic–inorganic hybrid biomaterials is the facilitation and control of adhesion at interfaces, as many current synthetic biomaterials are inert, lacking interfacial bioactivity. In this regard, the development of a simple, unified way to biofunctionalize diverse organic and inorganic materials toward biomineralization remains a critical challenge. In this report, a universal biomimetic mineralization route that can be applied to virtually any type and morphology of scaffold materials is provided to induce nucleation and growth of hydroxyapatite (HAp) crystals based on phase‐transited lysozyme (PTL) coating. Surface‐anchored abundant functional groups in the PTL enrich the interface with strongly bonded calcium ions, facilitating the formation of HAp crystals in simulated body fluid with the morphology and alignment being similar to that observed in natural HAp in mineralized tissues. By the adhesion of amyloid contained in the PTL, such protein assembly could readily integrate HAp on ceramics, metals, semiconductors, and synthetic polymers irrespective of their size and morphology, with robust bonding stability and corresponding ultralow wear extent under normal bone pressure. This strategy successfully improves the in vivo osteoconductivity of Ti‐based implant, underpinning the expectation for such biomaterial in future biointerface and tissue engineering.  相似文献   
999.
In this paper, a simple, but effective method is reported to construct the core?shell gold nanorod@metal–organic frameworks (AuNR@MOFs) as a multifunctional theranostic platform by using functionalized AuNRs as seed crystal for the growth of porphyrinic MOFs on the surface of AuNR. Such a delicate tunable core?shell composite not only possesses the improved drug loading efficiency, near‐infrared light‐trigger drug release, and fluorescence imaging, but also can produce reactive oxygen species as well as photothermal activity to achieve combined cancer therapy. It is further demonstrated that the camptothecin loaded AuNR@MOFs show distinctively synergistic efficiency for damaging the cancer cell in vitro and inhibiting the tumor growth and metastasis in vivo. The development of this high‐performance incorporated nanostructure will provide more perspectives in the design of versatile nanomaterials for biomedical applications.  相似文献   
1000.
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