摘要：We report on the ability to create complex 3D flower-like SiO2 in vitro via CaCO3 micropar- icles supported by polyethyleneimine mediated biosilicification under experimentally altered chemical influences. The morphology, structure, composition of the product have been inves- tigated with the X-ray photoelectron spectrum, scanning electron microscope, transmission electron microscope, and energy-dispersive spectroscopy. Tile overall morphologies could be controlled to shift from a characteristic network of flower-like silica sphere to a sheet-like structure by adjusting physical adsorption of different amount of polyethyleneimine onto the surface of the CaCO3 microparticles.

摘要：基于26GHz室内通信测量数据对人体阻挡衰减特性进行了研究。在Vogler多重刃形绕射场强计算的基础上，提出了包含二射线和四射线的多个人体阻挡绕射模型。结果表明，四射线人体阻挡衰减模型与实验数据非常吻合，信道测量带宽为1GHz时的人体绕射衰减略大于带宽为500MHz时的衰减。在人体沿发端（TX）和收端（RX）连线平移过程中，人体位于连线中间位置时衰减最小，人体离RX端最近时衰减最大。在多人体穿过视距线阻挡测量中，人体横向穿过视距线（人脸正面面向RX喇叭口）比人体侧向（人脸侧面面向RX喇叭口）穿过视距线时衰减大。此外，人体阻挡数目越多，衰减越大，人体阻挡数目每增加1人，阻挡衰减增加5-8dB。本文结果为分析26GHz人体衰减特性和该频段毫米波无线通信系统设计提供有用信息。

摘要：Although human-induced pluripotent stem cell-derived cardiomyocytes(hi PSC-CMs) have been used for disease modeling and drug discovery, clinically relevant three-dimensional(3D) functional myocardial microtissues are lacking. Here, we developed a novel ring-shaped cardiac microtissue comprised of chamber-specific tissues to achieve a geometrically non-orientable ventricular myocardial band, similar to a M?bius loop. The ring-shaped cardiac tissue was constructed of hi PSC-CMs and human cardiac fibroblasts(h CFs) through a facile cellular self-assembly approach. It exhibited basic anatomical structure,positive cardiac troponin T(c Tn T) immunostaining, regular calcium transients, and cardiac-like mechanical strength. The cardiac rings can be self-assembled and scaled up into various sizes with outstanding stability, suggesting their potential for precise therapy, pathophysiological investigation, and large-scale drug screening.

摘要：A small prototype of an active-target time projection chamber detector based on the gas electron multiplier(GEM) readout technique was designed and *** calculations were performed to analyze the electric field distribution and optimize the *** particular,a guard ring installed above the GEM foil may play an important role in shaping the electric field in the gas vessel and improving the overall performance of the *** best results were obtained at a guard-ring voltage of-950 *** using a collimated a-particle source,an energy resolution of 3.6–4.0 ke V can be achieved for deposited energies of 18–21 keV,respectively.A position resolution of less 0.2 mm was observed along the electron drift direction,whereas the resolution in the readout plane was approximately 0.45 mm.A time resolution of less than 20 ns was *** using helium as the primary working gas as well as the target material,a t a elastic scattering events can be clearly imaged.

摘要：Traditional feature-based turbine blade models can match the needs of geometric modeling but could hardly meet the requirement of data extraction in 1-D heat transfer analysis. In this paper, the requirements of data extraction in 1-D heat transfer analysis are taken into consideration as well as geometric representation in parametric design process. An improved turbine blade parametric modeling method is proposed. Based on the modeling method proposed, a system structure of blade modeling process considering 1-D heat transfer analysis is devised. Eventually, a turbine blade parametric modeling system is constructed to test and verify the feasibility of the proposed modeling method and system structure. Experiments show that the blade parametric modeling method proposed can make geometric models better adapt to the specific requirements of 1-D heat transfer analysis and has certain reference value to the creation of high quality digital models.

摘要：Objective： To summarize the clinical study on acupuncture treatment of hyperlipidemia for figuring out the existing issues and guiding the future study. Methods： Obtained by searching the scientific and technological journals database with computer, the relevant literature on acupuncture treatment of hyperlipidemia in the recent ten years is summarized and analyzed. Results and Conclusion： Forty-two pieces of the articles in conformity to the criteria of recruitment mainly refer to acupuncture, moxibustion, and simultaneous application of acupuncture and moxibustion, catgut-embedding method of the acupoints, external application of herbal products on the acupoints, and acupoint-injecting method, mostly by the acupoints of the Spleen and Stomach Meridians. But, the methods to select the acupoints by pattern identification, the application of the needling techniques and design of the test plans need to be further amended.

摘要：为了提高白光下人眼的视觉质量,设计了一款折射/衍射球柱有晶体眼人工晶体(PIOL)。根据实际人眼的角膜地形图、眼内各组分的轴向间距和波前像差,运用Zemax光学设计软件,构建了个性化眼模型;然后,运用该模型,设计了球柱PIOL和折射/衍射球柱PIOL。研究表明:与球柱PIOL相比,折射/衍射球柱PIOL能够全面提高人眼的白光调制传递函数(MTF)和非中心波长下的MTF,有利于获得良好的视觉质量。研究还表明:折射/衍射球柱PIOL只需要在4 mm区域设计二元面就能够满足要求。最后,分析了加工工艺问题。折射/衍射球柱PIOL在先进视觉矫正方面具有潜在的应用价值。

摘要：稳定、可靠的电量远程抄表一直是电力部门和电力运营商迫切解决的问题,而目前电量的远程抄表大都是基于人工或电力线载波、专用通信网实现,这些方案因各种原因均不能满足现代用电管理的要求。本文在分析已有方案的基础上,提出了一种基于S7600A的电量远程抄表系统的设计方案。该方案利用嵌入式TCP/IP协议芯片在实现In ternet接入方面的优势,能较好地解决资源有限的电能计量系统与In ternet连接的问题。文中探讨了相关的网络结构和较详细的设计思路。

摘要：由于微纳卫星反作用飞轮的输出力矩与气浮转台的干扰力矩属于同一量级,故无法直接采用气浮转台实现微纳卫星姿态动力学仿真及姿控系统的地面试验验证。为了解决这一问题,设计并研制了主动补偿式超低干扰力矩气浮转台。对气浮转台的干扰力矩进行分析,提出了3种减小干扰力矩的方法:通过优化设计,降低了黏滞阻尼力矩;通过配置斜向节流孔,并单独供气,产生大小可调的主动涡流以抵消气浮轴承的固有涡流,从而降低涡流力矩;利用气浮轴承的摆动特性实现高精度平衡调节,减弱了重力诱导力矩。最后,设计了微小力矩测量装置,测量了剩余干扰力矩并基于测试结果来指导涡流力矩和重力诱导力矩补偿过程。测试结果显示:气浮转台实现的干扰力矩小于5×10-5 Nm,小于反作用飞轮的最小输出1×10-4 Nm,满足微纳卫星姿态动力学及控制的地面验证需求。

摘要：详细介绍了我们自主开发的面向虚拟现实(VirtualReality,VR)通用应用开发的软件平台VRFlier。它基于市场上的成熟工具库和自建工具库构建,具有跨平台、模块化、易扩展等特点,能够较为全面地支持不同领域和不同规模的VR应用开发。本文详细介绍了VRFlier的概念模型、系统结构、交互仿真处理机制、主流程、应用开发过程等。最后,给出一个基于VRFlier开发的复合材料结构设计的应用实例。