Performance of a small high-speed liquid jet apparatus

The performance of a small high-speed liquid jet apparatus is described. Water jets of 200m/s to 700m/s have been obtained by firing a deformable lead slug from an air rifle into a stainless steel nozzle containing water sealed with a rubber diaphragm. Nozzle devices of using the impact extrusion (IE) method and cumulation (CU) method are designed to generate jets. The injection sequences are visualized using schlieren photography. The difference between the IE and CU methods in the jet generation is found

The Study and Design of Performance Evaluation System for R&D Employees in Fujian Kerui Pharmaceutical Co., Ltd.

福建科瑞药业有限公司是一家小型高科技制药企业，面对入世后竞争激烈的医药市场，必须提高企业的研发能力和核心竞争能力。本文针对科瑞公司研发工作现状，提出了研究的问题，即如何对研发人员绩效进行科学有效的考评，并设计新的研发人员绩效考评体系。 文章首先概述了绩效的涵义，绩效考评体系的概念、原则和程序，简要介绍了绩效考评的常见方法、指标体系、相应的权重体系和考评标准的设计原则和方法。其次，为了分析和评估公司现行的研发人员绩效考评体系，本文结合公司实际，设计了研发人员员工满意度调查问卷，并进行问卷调查。通过深入分析问卷调查结果，指出存在的问题。最后，论文设计了新的研发人员绩效考评体系。Fujian KeRui Pharmaceutical Co., Ltd. (FJKR) is a small high-tech pharmaceutical enterprise. Facing the keen competition in medicine market, FJKR should improve its R&D ability and core competitive capability. According to the existing R & D problems in FJKR, this paper discusses how to scientifically evaluate the performance of R&D employees in FJKR and designs a new performance evaluation syst...学位：工商管理硕士院系专业：管理学院工商管理教育中心_工商管理硕士(MBA)学号：X200115077

Rate Control Strategy Based on the Distributed Character of DCT Coefficients

根据缓存器的状态和信道速率为待编码帧在图像层上预分配目的视频编码比特数 ,使用DCT系数分布特性来表征图像特性 ,继而为帧内每一具体宏块选定最佳量化因子 ,提出了基于DCT系数分布特性的码率控制策略 .并分析了算法的复杂度 ,提出了改进策略 .模拟实验表明 ,该码率控制策略能有效地减少、避免缓存器出现上、下溢的情况 ,而输出码率趋于稳定 .提高了重建图像的信噪比 ,并且在视频图像质量没有明显失真的前提下 ,改进了计算复杂度 .Rate control strategy based on the distributed character of DCT coefficients is proposed , we allocates the target number of bits firstly on picture layer based on the status of the buffer and the channel rate, and then denotes the characteristics of the picture by the distributed characteristics of the DCT coefficients and select a best quantized parameter for every macroblock in a frame. The complexity of the algorithm is analyzed and an improved method is proposed. The experiment shows that this rate control strategy can effectively reduce and avoid the overflow and underflow of the encoder buffer, and the output bit rates tend to stabilization. The PSNR of the reconstructed picture is raised, and the complexity of the algorithm is improved with no visible distortion in video image.安徽省教委自然科学基金资助项目 (99j10 0 18

Research on the mechanics of underwater supersonic gas jets

An experimental research was carried out to study the fluid mechanics of underwater supersonic gas jets. High pressure air was injected into a water tank through converging-diverging nozzles (Laval nozzles). The jets were operated at different conditions of over-, full-and under-expansions. The jet sequences were visualized using a CCD camera. It was found that the injection of supersonic air jets into water is always accompanied by strong flow oscillation, which is related to the phenomenon of shock waves feedback in the gas phase. The shock wave feedback is different from the acoustic feedback when a supersonic gas jet discharges into open air, which causes screech tone. It is a process that the shock waves enclosed in the gas pocket induce a periodic pressure with large amplitude variation in the gas jet. Consequently, the periodic pressure causes the jet oscillation including the large amplitude expansion. Detailed pressure measurements were also conducted to verify the shock wave feedback phenomenon. Three kinds of measuring methods were used, i.e., pressure probe submerged in water, pressure measurements from the side and front walls of the nozzle devices respectively. The results measured by these methods are in a good agreement. They show that every oscillation of the jets causes a sudden increase of pressure and the average frequency of the shock wave feedback is about 5-10 Hz

Occurrence and Distribution of Organotin Compounds in Thais clavigera from Xiamen Coast

采用戊基化格式衍生法,gC-fPd分析了厦门港周边海域9个小岛屿分布的疣荔枝螺(THAIS ClAVIgErA)体内3种丁基锡化合物(buTylTInS)和3种苯基锡化合物(PHEnylTInS)的存在形态与分布特征.结果表明,丁基锡化合物总浓度(ΣbTS)为0.3~70.6ng.g-1,平均值为28.8ng.g-1,以一丁基锡化合物(MbT)为主.苯基锡化合物总浓度(ΣPHTS)为nd~18.8ng.g-1,平均值为7.9ng.g-1,以三苯基锡化合物为主.厦门港周边海域以丁基锡化合物为主要污染物,占到总有机锡化合物(ΣOTS)的74.3%~96.8%.疣荔枝螺体内(ΣbTS)和(ΣPHTS)呈现从厦门港内到港外逐渐降低的趋势.疣荔枝螺体内TbT和TPHT的浓度显示良好的相关关系(r2=0.7109,P<0.01),说明TPHT和TbT来源趋同,即来源于船舶防污涂料,或水产养殖污染源.与我国东南沿海港口相比,厦门海域疣荔枝螺体内丁基锡化合物的污染处于一个较低水平但比2002年有所加重.Occurrence and distribution of 6 organotin compounds including butyltin and phenyltin species were detected in Thais clavigera which were collected from 9 coastal areas sites around Xiamen Coast,by pentylized derivatization,GC-FPD.Results indicated that all Thais clavigera samples were contaminated with organotin compounds.The concentrations in Thais clavigera soft bodies varied from 0.3 to 70.6 ng.g -1 with a mean value of 28.8 ng.g -1 for butyltin compounds,and from nd to 18.8 ng.g -1 with a mean value of 7.9 ng.g -1 for phenyltin compounds,respectively.MBT and TPhT were high levels in butyltin compounds and phentyltin compounds,respectively.In addition,butyltin compounds were the dominant contaminates in all samples with high percentage from 74.3% to 96.8%.There was a significant correlation between TBT and TPhT (R2 = 0.710 9,p < 0.01).This result showed that both TBT and TPhT came from antifouling paints for ships or for mariculture nets.Compared with those data reported from the other regions around southeast coast of China,present study reveals that contaminated level of organotin compounds in Thais clavigera are relatively lower in Xiamen Coast.But it is higher than those in 2002.国家自然科学基金项目(40476048;20777060

骨髓间充质细胞联合PDMS支架构建移植胰岛微环境的实验研究

目的为了提高移植胰岛的活性和功能,构建适合移植胰岛生存的微环境。方法采用聚二甲基硅氧烷(PDMS)和氯化钠晶体构建三维支架,联合骨髓间充质细胞(MSCs)、纤维蛋白和胰岛共同构建迷你\"人工胰腺\"。采用链脲佐菌素(STZ)诱导的糖尿病大鼠移植模型评价效果,将\"人工胰腺\"移植到糖尿病大鼠大网膜内,对照组行假手术,术后隔天监测移植大鼠血糖水平;数据采用t检验和曼-惠特尼U检验。结果用PDMS构建的三维巨孔支架,支架内可见大量不规则孔洞空间。胰岛和MSCs可成功装载入支架内,HE染色结果显示,支架孔内存在胰岛,胰岛周围包绕有MSCs。糖尿病大鼠大网膜内移植结果显示,移植后各时间点(1,3,5,7 d),\"人工胰腺\"移植组糖尿病大鼠血糖水平分别为(278.70±86.06) mg/dl、(323.50±44.29) mg/dl、(283.30±74.00) mg/dl、(304.80±13.33) mg/dl,较假手术对照组(606.00±52.40) mg/dl、(589.70±55.78) mg/dl、(615.00±54.84) mg/dl、(630.30±48.17) mg/dl均降低,差异具有统计学意义(t=7.96、9.15、8.82,U=0.00,P均<0.01)。结论 MSCs联合PDMS三维支架构建的微环境,可为移植胰岛提供生存的环境,为临床开展胰岛移植提供新的策略

厦门市碘缺乏病防治现状与对策

[目的]了解碘缺乏病防治现状,探讨今后防治措施与策略。[方法]采用容量比例概率法抽查学生甲状腺大小、尿碘、盐碘,开展加工厂盐、居民户盐及盐民自用盐的盐碘含量监测。[结果]查2525名8～10岁学生,甲状腺肿大率为3.72%(触诊法),自1995年以来呈逐年下降趋势,合格碘盐食用率89.66%,碘盐覆盖率90.72%,尿碘中位数为246.40μg/L;加工厂盐合格率为99.15%,居民户碘盐覆盖率为95.25%、合格碘盐食用率为94.10%,盐民自供盐10月份后合格碘盐食用率已达到90%以上。[结论]我市继续保持在实现消除碘缺乏病阶段目标,但今后应坚持开展病情监测和坚持防制措施不松懈

Imposex of Thais clavigera and Cantharus cecillei in the coastal waters of Xiamen

海产腹足类性畸变以其对有机锡的敏感性、特异性和不可逆性而成为海洋有机锡污染的理想指示种。调查研究了厦门海域岩相海岸带疣荔枝螺(THAIS ClAVIgErA)和甲虫螺(CAnTHAruS CECIllEI)的性畸变情况,通过生物学指标IOI(性畸变率)、rPSI(相对阴茎发展指数)、VdSI(输精管发展指数)及SrI(性比指数)综合评价其性畸变发展程度,间接指示厦门周边海域的有机锡污染程度。研究结果发现,在采集疣荔枝螺的17个站点中有5个站点种群性畸变率为100%,其中宝珠屿种群性畸变程度最为严重,VdSI达4,采集甲虫螺的4个站点的种群性畸变率均为100%。性畸变程度较严重的种群普遍集中于厦门西港,并且表现出由港内到港外逐渐减轻的趋势,而白城、会展中心和大嶝岛等位于开阔的厦门东海域的种群性畸变程度最轻,与往年厦门西海域有机锡污染监测数据相比一致,体现出性畸变程度与有机锡污染程度及海港码头远近之间的相互关系。The degree of imposex,i.e.the imposition of male characteristics onto females,in neogastropods can be used as a sensitive and accurate biomarker to evaluate organotin contamination in coastal marine environment.Now,the imposex status in females of Thais clavigera and Cantharus cecillei in 17 sites was investigated to evaluate the organotin contamination along Xiamen Bay during 2006 and 2007.The four indices including incidence of imposex(IOI),relative penis size index(RPSI),vas deferens sequences index(VDSI) and sex ratio index(SRI) were used comprehensively to assess the imposex status in order to ascertain the extent of organotin bioavailability in Xiamen Bay.Based on this research,T.clavigera in 5 sites and C.cecillei in all survey sites exhibited the IOI of 100%.At Bao ZhuYu Islet,the imposex level was the most serious with maximum VDSI value of 4.In general,the imposex level decreased from the inner to the outer of Xiamen Western Harbour,and the populations in the open Xiamen Eastern Waters including Bai Cheng,Convention and Exhibiton Center and Dadeng Island showed a lower imposex level.These results were accordant with the concentrations of organotins in 2005.The imposex degree also increased with increasing organotin contamination and decreasing distance from shipping facilities.国家自然科学基金资助项目(40476048);厦门大学近海海洋环境科学国家重点实验室开放基金资助项目;厦门大学新世纪优秀人才计划基金资助项

Y型聚乙二醇干扰素琢-2b注射液治疗HCV基因2/3型慢性丙型肝炎患者疗效和安全性的多中心随机对照试验研究

目的以标准剂量的聚乙二醇干扰素(Peg IFN)α-2a联合利巴韦林作为阳性对照,评价新型试验药物Y型Peg IFNα-2b注射液联合利巴韦林治疗2型/3型慢性丙型肝炎(CHC)患者的疗效和安全性。方法采用多中心、随机开放、阳性药对照的Ⅲ期临床试验,筛选符合要求的2型/3型CHC患者,按照2:1的比例随机分配到Y型Peg IFNα-2b组和Peg IFNα-2a组,同时口服利巴韦林,疗程24 w,停药随访24 w。采用Abbott Real Time HCV Genotype II检测HCV基因型,采用Cobas Taq Man实时定量PCR法检测血清HCV RNA水平。详细记录不良事件。主要疗效指标为持续病毒学应答(SVR),并进行非劣效检验。结果本试验实际入组2型/3型CHC患者255例,实际治疗241例。全分析集(FAS)数据显示,158例试验组和83例对照组患者SVR分别为85.4%(95%CI 79.94%~90.94%)和79.5%(95%CI 70.84%~88.20%,P=0.2402);对符合方案分析集(PPS)人群分析显示,试验组和对照组患者SVR分别为87.9%(95%CI 82.45%~93.27%)和85.9%(95%CI 77.82%~94.01%,P=0.7060),率差的95%可置信区间均符合非劣效标准;对PPS人群分析显示,85.8%受试者获得了早期病毒学应答(RVR),RVR的阳性预测值为90.1%;试验组和对照组不良事件发生率相似,分别为95.6%和95.2%,严重不良事件发生率分别为3.8%和3.6%。结论应用Peg IFNα联合利巴韦林治疗2型/3型CHC患者,新型试验药物Y型Peg IFNα-2b具有与对照药物Peg IFNα-2a相似的疗效和安全性。国家科技部“十二五”重大专项(编号:2012ZX10002-003)；“重大新药创制”十二五科技重大专项(编号:2012ZX09303019)

流体界面RT和RM不稳定性发生装置

本发明公开了一种流体界面RT和RM不稳定性发生装置，该装置由管体组成，所述管体包括气体段和实验段，该气体段和实验段密封连接，其中气体段上端密封，实验段下端设有一隔膜。上述结构安装方便，结构紧凑，可以很方便快捷地实现流体界面的RT、RM两种方式的不稳定性模拟实验