摘要：The elliptical reflection zone plate is a kind of optical element in soft x-ray and x-ray ranges and has focusing and dispersion properties. Compared with a transmission zone plate, the required dispersion ordei, can be easily separated from zeroth order diffraction. It is fabricated on a bulk substrate and does not have much difficulty in the fabrication process. We design a 1000-zone off-axis elliptical reflection zone plate for the rnonochromatization of the ultrafast betatron radiation at the low energy band, at the designed wavelength of 2.478 nm （500eV） which is an important spectral part of the betatron radiation, with high spatial resolution, high spectral resolution. Moreover, we simulate the designed reflection zone plate properties. The simulation results show that the spatial resolutions in the spatial direction and the spectral direction are 6.4μm and 7.3μm （full width half maximum）, respectively,, and the spectral resolution reaches up to 496 for the well aligned point source system, which is in good agreement with the theoretical predictions. In addition, we discuss some factors influencing the spectral and spatial resolution, such as the zone number, zone area and the incidence wavelength. The elliptical reflection zone plate also has potential applications in investigating x-ray fluorescence spectra and other fields.

摘要：Deinococcus radiodurans' high resistance to various stressors combined with its ability to utilize sustainable carbon sources makes it an attractive bacterial chassis for synthetic biology and industrial bioproduction. However, to fully harness the capabilities of this microbe, further strain engineering and tool development are required. Methods for creating seamless genome modifications are an essential part of the microbial genetic toolkit to enable strain engineering. Here, we report the development of the SLICER method, which can be used to create seamless gene deletions in D. radiodurans. This process involves (a) integration of a seamless deletion cassette replacing a target gene, (b) introduction of the pSLICER plasmid to mediate cassette excision by I-SceI endonuclease cleavage and homologous recombination, and (c) curing of the helper plasmid. We demonstrate the utility of SLICER for creating multiple gene deletions in D. radiodurans by sequentially targeting 5 putative restriction-modification system genes, recycling the same selective and screening markers for each subsequent deletion. While we observed no significant increase in transformation efficiency for most of the knockout strains, we demonstrated SLICER as a promising method to create a fully restriction-minus strain to expand the synthetic biology applications of D. radiodurans, including its potential as an in vivo DNA assembly platform.

摘要：This paper demonstrates the analysis of antenna pattern and gain for different designs of full-wave dipole antenna feeding techniques. Seven such techniques were studied and analyzed;symmetrical dual feeding in phase, symmetrical dual feeding out of phase, asymmetrical dual feeding in phase, asymmetrical dual feeding out of phase, symmetrical triple feeding in phase and symmetrical triple feeding out of phase. Symmetrical dual feeding in phase produced high gain as compared to the single and center-fed antennas. An improvement of about 3 to 3.5 dB was achieved comparing to center tap fed and off center fed. It was found that an asymmetrical dual feeding in-phase provides good performance, considering the directivity, pattern, and input impedance. A 2.46 dB gain has been attained. It was found that a symmetrical triple feeding provides an overall best performance with respect to gain, radiation pattern, beam width and input impedance.

摘要：纽扣电极型探头主要用于束流横向位置测量,在拾取束流信号的同时会存在发热形变问题,有可能引入额外的系统测量误差,极端情况下甚至会导致设备损坏,在强流电子储存环的设计和运行中对此问题需要加以研究。介绍了上海光源储存环纽扣电极的束流负载热效应的分析建模方法,对不同束流流强、不同填充模式下的电极发热问题进行了ANASYS仿真分析。结果表明,在上海光源所有设计运行模式下,电极因束流负载引起的发热形变均小于加工公差,对位置测量的影响可基本忽略,但极端情况下探头内的温度可达270°C,存在一定的设备损坏风险,需要提出相应对策。

摘要：In this paper, we propose a new design procedure for printed dipole array antennas. Applications of these arrays are devoted to wireless communication systems, mainly base stations and beam steerable antennas. All the designs have been developed at the frequency of 3 GHz. This structure is chosen in order to enhance the gain and minimize the backside radiations of an antenna array with a very simple feeding.

摘要：The objective of the present article is to find an optimal design of a fan inlet to reduce the amount of noise radiated to the far field from the system. Against the gradient-based optimization algorithms, we employ here a method based on measure theory which does not require any information of gradients and the differentiability of cost function.

摘要：In this paper, the evolutionary algorithm of particle swarm optimization (PSO) is applied to synthesis an optimal linear array in the Chebychev sense. Equiripple radiation patterns may be obtained by synthesizing the excitation currents feeding the array or by carefully choosing the interelement spacing. The desired equal side lobes level is achieved simultaneously with the narrowest possible beamwidth (high directivity). Though the optimization problem may become nonlinear, convex and/or sometimes nonconvex, it can be handled using an efficient, a robust and a nongradient based particle swarm optimizer algorithm. In order to effectively utilize this algorithm it is important to define an appropriate objective, or cost, function that return a single number to enable the PSO algorithm minimizing it. In this paper, the objective function is formulated taking into consideration the level of the side lobes as well as the main beam width. In addition to satisfy the objective function, the obtained results using the proposed technique are in agreement with those available in the literature.

摘要：Solar collectors can provide clean, renewable, and domestic energy. The tilt angle and horizontal direction of solar collectors significantly affect its efficiency. There are many good methods to search the optimum tilt angle and horizontal direction to realize the maximum total radiation on the solar collector within a particular day or a specific period. However, it is hard to realize it when solar collectors are placed under obstacle’s shadows;especially when some obstacles, such as trees, have irregular shapes. This paper presents algorithms to achieve the best tilt angle and horizontal direction for solar collector’s performance under the free-form surfaces 3D obstacle’s shadow. The solution process is composed of 4 steps. First, it creates a 3D scene, in which a unique color is given to the solar collector. Second, it employs orthographic projection from the point of view to get an image of the scene. Third, the number of pixels is used to represent the efficiency of the solar collector by counting the pixels of the unique color. Fourth, the efficiency of solar collector in each direction in a period of time is calculated with many images to further select the best direction.

摘要：建立以光伏电池在寿命期内总利润最大的数学模型,展开对太阳光直射、散射和反射辐射量的分析,获得理论上的最大赢利方案,再结合小屋墙面和屋顶的形状,选取光伏电池的最优安装方式。针对架空方式安装光伏电池,以总辐射最大为目标,确定了安置光伏电池的最佳倾角。在此基础上设计新的太阳能小屋,并在满足相关建筑要求的前提下,取得了优化的效果。

摘要：目的：探讨ⅡB期宫颈癌全盆盒式放疗与不同射野调强放疗（ IMRT）的剂量学差异，并比较临床疗效及急性毒副反应。方法收集10例ⅡB期宫颈癌患者进行CT模拟定位，每例患者均设计全盆盒式放疗计划和3种不同设野的IMRT计划，评估靶区及危及器官的剂量。回顾性分析2011年1月至2012年10月收治的77例ⅡB期宫颈癌初诊患者，根据患者意愿分为盒式放疗组（n＝33）及IMRT组（n＝44），分别采用盒式放疗（46～50Gy）或9野IMRT（56Gy／28f）结合后装腔内放疗并同步顺铂（25mg／m2静滴，每周1次，共5～6次）化疗，比较近期疗效及急性毒副反应。结果3种不同射野IMRT计划中计划靶区体积（PTV）的靶区均匀性（HI）和适形性（CI）均优于盒式放疗计划（P＜0.05），膀胱V30、V40、小肠V20、V30、V40、Dmean、D50及直肠V30、V40、Dmean、D50均低于盒式放疗计划（ P＜0.05）；3种IMRT之间PTV的HI及CI的差异无统计学意义，随着照射野的增多，膀胱V30、V40、Dmean、D50及直肠V20、V30、V40、Dmean、D50逐渐下降，其中膀胱V30、V40差异有统计学意义（ P＜0.05）。盒式放疗组与IMRT组完全缓解率分别为84.8％及88.6％（ P＞0.05）。 IMRT组放射性肠炎、放射性膀胱炎的发生率低于盒式放疗组（ P＜0.05），两组均出现不同程度骨髓抑制，但差异无统计学意义（ P＞0.05）。结论 IMRT计划在剂量学上显示了保护危及器官的优势，在临床疗效上9野IMRT与盒式放疗的近期疗效相当，但能明显降低急性毒副反应的发生率，推荐ⅡB期宫颈癌患者外照射行9野IMRT。