有机磷化合物的结构与迟发性神经毒性关系的研究

有机磷化合物（包括Ｉ型和Ⅱ型）对人和其它脊椎动物诱导迟发性神经毒性,日益引起人们的关切。此类化合物种类繁多,结构各异。那么,哪些可能产生迟发性神经毒性？本文就此问题论述了该类化合物的结构与迟发性神经毒性的关系。     

Microbial community-assisted water quality control and nutrients recovery: emerging technologies for the sustainable development of aquaponics

Aquaponics is considered as a possible method to produce aquatic animals and plants in an environmentally-friendly way, but its commercialization is seriously hindered owing to some technical and economic problems. Recently, the integration of microbial community with aquaponics is on the way to becoming the next-generation technology for the sustainable development and commercialization of the aquaponics industry. This article provides an authoritative discussion on the novel microbial community-assisted aquaponics, which will be emerging from the research environment to industrial application in the coming future. Principles and key technologies of this novel aquaponics, as well as the potential challenges to its commercialization, are discussed. It is expected that the emerging technologies discussed in this work could address the existed technical problems and further promote the commercialization of aquaponics. © 2019 Society of Chemical Industry     

一种改进的无线光通信LDPC码译码算法

针对无线光通信中低密度奇偶校验码(LDPC)置信传播(BP)译码算法复杂度高及置信度振荡造成译码错误等缺点,基于对数BP算法提出了一种改进的译码算法。改进的译码算法在校验节点运算时,判断输入到校验节点消息的最小值与某个门限的大小,根据比较结果,分别用消息最小值或若干个最小值进行运算,在损失很少性能的情况下降低了运算复杂度;同时在比特节点采用振荡抵消处理运算,提高了算法的性能增益。最后在对数正态分布湍流信道模型下,分别对比特充分交织和交织深度为16的情况进行了仿真实验。仿真结果表明,改进的译码算法与BP算法相比,大幅度降低了计算复杂度,而且译码性能有一定的优势,收敛速度损失很少;而相对于最小和算法,改进的算法虽然译码复杂度有所增加,但误码率性能有明显的优势,并且收敛速度也优于最小和算法。因此,改进的译码算法是无线光通信中LDPC码译码算法复杂度和性能之间一个较好的折中处理方案。     

南堡联合站轻烃回收工艺参数优化研究

目的提高南堡联合站天然气轻烃回收率,降低生产能耗。 方法基于HYSYS模拟软件建立模型,分别对天然气轻烃回收工艺的增压单元、冷冻分离单元、轻烃分馏单元等关键参数进行单因素分析。 得出各单因素的取值范围;依据各单因素的取值范围,以系统回收装置最小比功耗为目标函数,利用响应面分析法对参数进行优化,确定多因素关键参数的最佳组合。 结果优化后的流程比实际生产丙烷收率提升了5.62%,液化气产量提升了3.53%,产品比功耗减少了0.91%,装置总能耗降低了2.46%。结论响应面分析法用于天然气轻烃回收的各参数优化,提高了丙烷收率,降低了装置能耗,具有很好的经济性和应用前景。      

Resolving the Interface of Calcium Phosphate Formation on the Porous Bioceramics In Vitro

Porous bioceramics have been widely studied for bone tissue engineering. A deep understanding on the mechanism of bone growth and biomineralization depends on the extracted interface information between the new precipitated calcium phosphates (CaPs) and the porous substrate at a nanometer scale. However, due to their intrinsic brittleness and the complexity of the sample shape, there is still lack of such information. Here, by a combination of focused ion beam (FIB) and transmission electron microscopy (TEM), in‐situ cross‐sectional electron transparent interface was prepared. The precipitated dense apatite layer is composed of individual microgranules which further consist of tiny flake‐like crystals. The new crystallites grow along c‐axis and are mostly oriented perpendicular to HA substrate. This preferred orientation is more pronounced in the presence of protein. This work offers a novel and feasible approach using FIB‐TEM to in situ image porous bioceramic scaffold and precipitated apatite layer interface and can be extended to study many other biointerfaces.     

Millifluidic synthesis of polymer core‐shell micromechanical particles: Toward micromechanical resonators for acoustic metamaterials

We present two routes of millifluidic‐based synthesis of solid core–solid shell particles with submillimeter size. These particles, which behave as mechanical resonators, are key components of targeted three‐dimensional locally resonant acoustic metamaterials working in the ultrasonic frequency range. The first route involves the encapsulation of a solid core into a liquid shell, which is then in‐line solidified through gelation. The second route involves two successive coflows followed by two solidifications triggered by UV irradiation and complexation, respectively. Original solutions to several practical issues are presented. The advantages and drawbacks of both routes are analyzed in the light of the targeted specifications of the resonators. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

多球中子探测器能量响应特性的研究

本文描述多球中子探测器的能量响应特性。慢化球由密度为0.93克/厘米~3的聚乙烯制成,直径在5.1—24.4厘米之间。中心置—φ1.9×8厘米的 BF_3正比计数器,充气压为70厘米汞柱,~(10)B丰度约为95%。当工作电压为1500伏时,分辨率约为20%,本底约为0.4计数/分,热中子灵敏度为0.5计数/(中子·厘米~(-2))。测量所使用的中子能量范围在热能—15兆电子伏之间。0.02—15兆电子伏能区的能量响应曲线直接按实验值绘出;热能—0.02兆电子伏能区的响应曲线,则根据实验值及 D.Nachtigall给出的 M65数据推算。所得结果与报道的理论值作了比较,对于较小的慢化球探测器,理论值存在较大的误差,例如对直径为7.6厘米的慢化球探测器,在10电子伏处,理论值(M.P.Dhairyawan et al.,1980;R.E.Maerker et al,1971)为实验内插值的2倍。     

电容储能式冲击实验电流发生器及程控技术

介绍自行设计的一种冲击实验电流信号发生器的基本原理与技术方案。该设备采用电容储能放电原理,通过程控大电流电子开关切换,产生kA级的脉冲电流,用在诸如雷电闪络传感器的测试、霍尔元件特性的动态分析和快速充磁电流源、或在电路系统实验室中作为激励信号源,用于RLC元件的动态电路特性分析一类的科研、教学实验中。因工作电压很低,具有安全、可靠和成本低廉等优点。