924 resultados para Specification


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As a kind of waste collected from restaurants, trap grease is a chemically challenging feedstock for biodiesel production for its high free fatty acid (FFA) content. A central composite design was used to evaluate the effect of methanol quantity, acid concentration and reaction time on the synthesis of biodiesel from the trap grease with 50% free fatty acid, while the reaction temperature was selected at 95 degrees C. Using response surface methodology, a quadratic polynomial equation was obtained for ester content by multiple regression analysis. Verification experiments confirmed the validity of the predicted model. To achieve the highest ester content of crude biodiesel (89.67%), the critical values of the three variables were 35.00 (methanol-to-oil molar ratio), 11.27 wt% (catalyst concentration based on trap grease) and 4.59 h (reaction time). The crude biodiesel could be purified by a second distillation to meet the requirement of biodiesel specification of Korea.

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This paper describes an attractive method to make biodiesel from soybean soapstock (SS). A novel recovery technology of acid oil (AO) from SS has been developed with only sulfuric acid solution under the ambient temperature (25 +/- 2 degrees C). After drying, AO contained 50.0% FFA, 15.5% TAG 6.9% DAG 3.1% MAG 0.8% water and other inert materials. The recovery yield of AO was about 97% (w/w) based on the total fatty acids of the SS. The acid oil could be directly converted into biodiesel at 95 degrees C in a pressurized reactor within 5 hours. Optimal esterification conditions were determined to be a weight ratio of 1 : 1.5 : 0.1 of AO/methanol/sulfuric acid. Higher reaction temperature helps to shorten the reaction time and requires less catalyst and methanol. Ester content of the biodiesel derived from AO through one-step acid catalyzed reaction is around 92%. After distillation, the purity of the biodiesel produced from AO is 97.6% which meets the Biodiesel Specification of Korea. The yield of purified biodiesel was 94% (w/w) based on the total fatty acids of the soapstock.

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叶酸是B族维生素的一员,参与体内一系列重要的生命过程包括DNA,氨基酸的合成,调控细胞周期,参与一碳单位供体循环,调节DNA,蛋白质甲基化等。叶酸的许多功能都和叶酸结合蛋白有关,体内有多种跨膜形式的叶酸结合蛋白,比如Folbp1,RFC,HCP等。以前的研究表明这些不同的叶酸结合蛋白具有不同的功能。分泌型叶酸结合蛋白是另外一类叶酸结合蛋白,在人类,小鼠,猪中都有序列报道,但是其功能却知之甚少。 我们在非洲爪蛙中鉴定出一个全新的分泌型叶酸结合蛋白并命名为Secreted Folate Binding Protein(sFBP)。在胚胎和转染细胞系中我们都证明该蛋白是分泌性的,表面等离子共振实验发现sFBP能够结合叶酸。在胚胎早期这个基因表达于粘液腺和神经板区域,神经管闭合后在神经管、粘液腺、眼睛,头部以及鳃弓都有表达。特异morpholino 阻断sFBP翻译后发现粘液腺发育异常,神经管闭合缺陷,前后体轴聚集延伸运动受到抑制,尾芽期胚胎表现出体轴缩短,无眼,小头或无头的表型。进一步研究发现显微注射sFBP morpholino 的胚胎神经板区域细胞发生凋亡,中胚层和神经外胚层的一系列粘附分子表达异常,神经细胞的正常分化也受到抑制。通过显微移植实验我们还发现抑制sFBP的翻译后,神经嵴细胞的正常分化和迁移都受到抑制。但是,显微注射叶酸及其类似物或者显微注射甲基供体S-腺苷甲硫氨酸或者亮氨酸甲基转移酶都不能挽救阻断sFBP造成的表形,由此提示sFBP可能不是通过叶酸传统的参与营养合成或者甲基化的途径发挥作用。我们发现注射sFBP morpholino可以抑制Islet-1mRNA和蛋白质的表达,Islet-1的表达区域与sFBP类似。共同注射Islet-1 mRNA和sFBP morpholino可以极大的挽救sFBP morpholino的表型。最后通过morpholino特异阻断Islet-1的表达后,我们发现其表现出与sFBP morpholino类似的粘液腺发育缺陷,神经板细胞凋亡,小头无眼的表形。由此叶酸是B族维生素的一员,参与体内一系列重要的生命过程包括DNA,氨基酸的合成,调控细胞周期,参与一碳单位供体循环,调节DNA,蛋白质甲基化等。叶酸的许多功能都和叶酸结合蛋白有关,体内有多种跨膜形式的叶酸结合蛋白,比如Folbp1,RFC,HCP等。以前的研究表明这些不同的叶酸结合蛋白具有不同的功能。分泌型叶酸结合蛋白是另外一类叶酸结合蛋白,在人类,小鼠,猪中都有序列报道,但是其功能却知之甚少。 我们在非洲爪蛙中鉴定出一个全新的分泌型叶酸结合蛋白并命名为Secreted Folate Binding Protein(sFBP)。在胚胎和转染细胞系中我们都证明该蛋白是分泌性的,表面等离子共振实验发现sFBP能够结合叶酸。在胚胎早期这个基因表达于粘液腺和神经板区域,神经管闭合后在神经管、粘液腺、眼睛,头部以及鳃弓都有表达。特异morpholino 阻断sFBP翻译后发现粘液腺发育异常,神经管闭合缺陷,前后体轴聚集延伸运动受到抑制,尾芽期胚胎表现出体轴缩短,无眼,小头或无头的表型。进一步研究发现显微注射sFBP morpholino 的胚胎神经板区域细胞发生凋亡,中胚层和神经外胚层的一系列粘附分子表达异常,神经细胞的正常分化也受到抑制。通过显微移植实验我们还发现抑制sFBP的翻译后,神经嵴细胞的正常分化和迁移都受到抑制。但是,显微注射叶酸及其类似物或者显微注射甲基供体S-腺苷甲硫氨酸或者亮氨酸甲基转移酶都不能挽救阻断sFBP造成的表形,由此提示sFBP可能不是通过叶酸传统的参与营养合成或者甲基化的途径发挥作用。我们发现注射sFBP morpholino可以抑制Islet-1mRNA和蛋白质的表达,Islet-1的表达区域与sFBP类似。共同注射Islet-1 mRNA和sFBP morpholino可以极大的挽救sFBP morpholino的表型。最后通过morpholino特异阻断Islet-1的表达后,我们发现其表现出与sFBP morpholino类似的粘液腺发育缺陷,神经板细胞凋亡,小头无眼的表形。由此我们认为sFBP结合叶酸后可能通过细胞膜上的受体传递信号,并且Islet-1可能在sFBP的下游发挥作用。 神经嵴是脊椎动物特有的一群多潜能干细胞,产生于表皮和神经板的边界,在原肠运动之后这群细胞通过表皮间充值转换从神经管背侧迁移到不同的区域,分化成不同的细胞类型,包括外周神经系统,色素细胞,软骨等。神经嵴的发生是一个多步骤多基因参与的精细调控过程。目前理论认为最初由一些分泌性信号分子又叫形态生成素比如BMP,Wnt,FGF,Notch等通过不同浓度梯度的相互作用调节一组在表皮和神经板边界的转录因子(Msx、Pax3/7、Zic1、Dlx3/5等)的表达,即边界决定。这些边界决定因子进一步在预定形成神经嵴的区域激活神经嵴特化基因比如Slug/Snail、FoxD3、Twist、Sox9/10的表达完成神经嵴的特化(Specification)。 Nkx6.3是Nkx6家族的一个转录因子,RT-PCR显示其呈现母源性表达。特异抗体显示Nkx6.3蛋白第9期在整个胚胎都表达,大部分蛋白集中在细胞核,有少部分蛋白定位于细胞膜上;神经板时期主要定位于神经嵴区域的细胞膜上。过表达Nkx6.3会影响细胞粘连分子的表达,由此干扰正常的胚胎原肠运动和Activin诱导的动物帽聚集延伸运动。显微注射Nkx6.3特异morpholino阻断其蛋白表达会抑制神经嵴的marker基因Wnt8,Fgf8,Pax3,Msx1,Zic1,FoxD3,Slug的转录,阻碍神经嵴的发育。在动物帽中单独注射Nkx6.3可以在mRNA水平上诱导Wnt8、Fgf8另一方面抑制BMP4的表达进而诱导神经嵴基因Pax3,Zic1,Slug的表达。报告基因实验也显示Nkx6.3能够激活Wnt信号而在动物帽中抑制BMP信号。Nkx6.3蛋白功能域分析发现其EH1结构域(domain)参与对Wnt8信号的激活,而EH1结构域和HD结构域之间的连接区域(linker domain)参与对FGF的激活和对BMP的抑制。进一步在动物帽和胚胎中分析发现Nkx6.3对Wnt8的激活依赖于FGF家族受体信号但是不依赖于Fgf8。有趣的是4细胞时期过表达Nkx6.3促进Fgf8和Wnt8 mRNA表达,但是抑制边界决定基因Msx1、Pax3和神经嵴特化基因Slug的转录。在32细胞时期显微注射Nkx6.3可以在内源神经嵴发生区域抑制Slug的表达,而异位却诱导Slug的mRNA。我们发现与动物帽中对BMP的调节不同,在胚胎中,过表达Nkx6.3会强烈的激活Smad1蛋白在细胞核中的表达即BMP信号被激活,高的BMP信号会抑制神经嵴的发生。另外我们发现过表达Nkx6.3在胚胎中抑制Dlx5而在动物帽中却不影响Dlx5的表达水平,Morpholino阻断Dlx5会抑制Msx1、Pax3和Slug的表达。BMP信号和Dlx5在动物帽和在整体胚胎中对Nkx6.3的不同响应可以一定程度上解释过表达Nkx6.3在2个系统中对神经嵴基因Slug相反的影响结果。

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This paper presents the total dose radiation performance of 0. S^m SOI CMOS devices fabricated with full dose SIMOX technology. The radiation performance is characterized by threshold voltage shifts and leakage currents of transistors and standby currents of ASIC as functions of the total dose up to 500krad(Si) .The experimental results show that the worst case threshold voltage shifts of front channels are less than 320mV for pMOS transistors under off-gate radiation bias at lMrad(Si) and less than 120mV for nMOS transistors under on-gate radiation bias. No significant radiation-induced leakage current is observed in transistors to lMrad(Si). The standby currents of ASIC are less than the specification of 5μA over the total dose range of 500krad(Si).

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Portlet是具有用户界面的可与用户多次交互的Web组件。随着Portal和Portlet在企业中的广泛应用,仅仅将各种应用和数据通过Portlet集成到Portal中已经不能满足用户的需求。用户希望这些应用之间能够相互协作,以利用现有应用组建新的业务流程。Portlet协作是指两个或多个Portlet进行信息交换并使用这些信息的能力。目前协作功能的实现方式可以分为两种:基于后端(back-end)的实现方式与基于前端(front-end)的实现方式。在这两种协作实现方式的基础上,本文提出了两种Portlet协作框架。 本文提出一种基于事件的Portlet前端协作模型,通过引入此模型,解决了Portlet前端协作中客户端与服务器端无法交互的困难,使协作动作由客户端和服务器端共同完成。基于此模型提供给开发者一种可扩展的协作框架,利用JavaScript技术使得协作的Portlet在客户端“相知”,协作的行为在客户端触发,Portlet获得协作数据后使用Ajax技术请求服务器端的资源,服务器端使用JSR286规范定义的资源服务接口响应用户的请求,进而动态更新界面。 当前的Portlet后端协作方式依赖于特定的Portal产品,针对这点不足,本文在JSR286规范定义的事件及共享渲染参数协作机制基础上,实现了一个Portlet后端协作框架。在该框架中协作服务使用消息队列保存待处理的消息,Portlet 容器作为中介实现发布事件的Portlet和订阅事件的Portlet之间松散耦合。Portlet监听协作事件,事件触发后调用事件协作服务发布事件,为了提高协作的并发性,事件协作服务使用多线程处理协作事件。该协作框架与JSR286规范兼容,具有良好的可移植性。 本文对这两种Portlet协作框架进行了实现,并将其应用于中科院软件所自主开发的门户产品OncePortal中。本文重构了OncePortal系统,给出了框架的体系结构与系统接口,描述了框架的各功能模块,并详细讨论了Portlet协作框架中的关键技术,包括事件协作流程的描述、事件处理过程、多级事件流等。

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编译器是软件产业中重要的工具,对它的质量保证非常重要。编译优化是编译器的重要功能,它的质量对于编译器质量有重大影响。可采用软件测试的方法进行编译器优化模块的质量保证。测试需要测试用例。编译优化的测试用例必须触发编译器的优化功能,是具有可被优化特征的源程序。对不同的编译优化,该特征各不相同。需要将不同优化所对应的特征加入到源程序中以构造编译优化测试用例程序。 TRANS语言结合了时序逻辑,描述了不同的编译优化,包括优化前后的代码特征、优化执行的条件及方法。优化前的代码特征和执行优化的条件可被用作构造编译优化测试用例程序所需的特征。一种基于时序逻辑的编译优化测试用例程序生成方法的框架已被提出。该方法从TRANS描述的某种变体生成编译优化测试用例程序。但是该框架并未完善,面临多方面的问题。本文参考该框架的思想,设计了编译优化测试用例程序生成方法,解决了算法框架的部分问题。该方法可以适应复杂描述的情况;公式的合法性及语义得以保持;具体化并完整化了原有框架。该方法是具有针对性的编译优化测试用例程序自动生成方法。本文对该方法作了原型系统实现,并从中得到测试用例程序。本文设计并进行针对GCC的优化模块测试实验,以覆盖率为评价指标检验了测试用例程序的质量。实验表明该方法生成的测试用例程序具有针对性。对编译优化模块的测试,该方法是一种行之有效的办法。并且该方法仍有更多的应用空间,加以改进后可用于优化组合测试、优化正确性检测等。

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For the purpose of manufacturing cigarette filter tows and filter rods, the melt-spinning, adhesion and adsorption properties of poly(lactic acid) were studied. The rheological measurements were performed to examine the effects of various processing conditions on the melt flowability and spinnability, including those of residual moisture. The melt spinning and post-processings were followed by determining the molecular weight, thermal and mechanical properties of the fibers. The results obtained were useful to establishing the specification of the PLA resins for filter tows and filter rods manufacturing and to choosing proper melt-spinning and post-processing technologies.

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Specification and differentiation of skeletal muscle cells are driven by the activity of genes encoding members of the myogenic regulatory factors (MRFs). In vertebrates, the MRF family includes MyoD, Myf5, myogenin, and MRF4. The MRFs are capable of converting a variety of nonmuscle cells into myoblasts and myotubes. To better understand their roles in fish muscle development, we isolated the MyoD gene from flounder (Paralichthys olivaceus) and analyzed its structure and patterns of expression. Sequence analysis showed that flounder MyoD shared a structure similar to that of vertebrate MRFs with three exons and two introns, and its protein contained a highly conserved basic helix-loop-helix domain (bHLH). Comparison of sequences revealed that flounder MyoD was highly conserved with other fish MyoD genes. Sequence alignment and phylogenetic analysis indicated that flounder MyoD, seabream (Sparus aurata) MyoD1, takifugu (Takifugu rubripes) MyoD, and tilapia (Oreochromis aureus) MyoD were more likely to be homologous genes. Flounder MyoD expression was first detected as two rows of presomitic cells in the segmental plate. From somitogenesis, MyoD transcripts were present in the adaxial cells that give rise to slow muscles and the lateral somitic cells that give rise to fast muscles. After 30 somites formed, MyoD expression decreased in the somites except the caudal somites, coincident with somite maturation. In the hatching stage, MyoD was expressed in other muscle cells and caudal somites. It was detected only in muscle in the growing fish.

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机器人研磨抛光工艺研究建立在大量机器人磨抛试验的基础上。本文针对加工对象——有机玻璃,在满足被加工工件质量的前提下,确定了机器人研磨抛光加工时磨片的合理使用顺序、规划加工路径和安排正交试验,以获得机器人磨抛加工的最优工艺参数组合,并制定机器人磨抛的加工策略。最后通过机器人研磨抛光加工实例,进一步验证了机器人的研磨抛光工艺知识有其合理性。

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为提高理性遗传算法遗传信息的完备性、算法全局收敛性以及算法的整体结构,给出了一个更一般化的理性算子和算法结构,证明了算法的全局收敛性.理论分析和在运动规划问题中的应用结果验证了理性遗传算法的有效性.

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本文在分析装配型AGVS系统和运输型AGVS系统的基础上,详细说明AGVS主要技术指标,性能特点和应用原则。同时,结合分析自动导引车的发展历史,说明自动导引车系统的应用领域,分析推测自动导引车的发展前景。

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根据领域中专用短程通信()协议的基础规范,设计出应用于电子收费系统的物理层、数据链路层和应用层相关参数ITSDSRCDSRC选定和设置。力求在电子收费领域相关的装置与设备能遵循指定的规格标准,并增进各系统相互之间的相容性和互连性。

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The seismic data acquisition system is the most important equipment for seismic prospecting. The geophysicists have been paying high attention to the specification of the equipment used in seismic prospecting. Its specification and performance are of great concerned to acquire precisely and accurately seismic data, which show us stratum frame. But, by this time, limited by the technology, most of the Broad-band Seismic Recorder (BSR) for lithosphere research of our country were bought from fremdness which were very costliness and maintained discommodiously. So it is very important to study the seismic data acquisition system.The subject of the thesis is the research of the BSR, several items were included, such as: seismic data digitizer and its condition monitor design.In the first chapter, the author explained the significance of the implement of BSR, expatiated the requirement to the device and introduced the actuality of the BSR in our country.In the second chapter, the collectivity architecture of the BSR system was illustrated. Whereafter, the collectivity target and guideline of the performance of the system design were introduced. The difficulty of the system design and some key technology were analyzed, such as the Electro Magnetic Compatibility (EMC), system reliability technology and so on.In the third chapter, some design details of BSR were introduced. In the recorder, the former analog to digital converter (ADC) was separated from the later data transition module. According to the characteristic of seismic data acquisition system, a set high-resolution 24-bit ADC chip was chosen to the recorder design scheme. As the following part, the noise performance of the seismic data channel was analyzed.In the fourth chapter, the embedded software design of each board and the software design of the workstation were introduced. At the same time the communication protocol of the each module was recommendedAt the last part of this thesis, the advantages and the practicability of the BSR system design were summarized, and the next development items were suggested.

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Organizations are increasingly turning to team-based structures to contend with the pressure of the increasing global competition, consolidation, innovation and need for diverse skills, expertise, and experiences. This ongoing transformation in the basic organization of work has captured the attention of researcher. And group and team research has become increasingly centered in the fields of organizational psychology and organizational behavior since the 1990s. A great deal empirical studies were conducted; a number of variables contributing to team effectiveness and several IPO models were summarized. But teamwork behaviors, the dynamic and adaptive interactions among team members during the task completion, were still very vague. So were the team task characteristics, an important input variable of the IPO models. The effects of team task characteristics and teamwork behaviors on team effectiveness were explored according to IPO model on the basis of the reviews on previous studies, the Hierarchical Conceptual Structure of Teamwork Behaviors (Rousseau et al.,2006), and the task characteristic theory(Hackman & Oldman, 1975). The questionnaire data from 479 team members and 110 team managers of 22 organizations were analyzed. The results indicate: A. Teamwork behaviors consist of 13 behavioral dimensions: team mission analysis, goal specification, planning, coordination, cooperation, information exchange, performance monitoring, backing-up behaviors, intra-team coaching, collaborative problem solving, team practice innovation, psychological support and integrative conflict management. The hierarchical conceptual structure was partly supported with five variable identified, i.e., preparation of work accomplishment, task-related collaborative behaviors, work assessment behaviors, team adjustment behaviors and the management of team maintenance. The formal four variables are in a sequential way. B. The task characteristic theory at individual level is applicable to the team level. This means that the team task characteristics consist of task variety, identity, significance, feedback, autonomy, interdependence. C. The correlations among task characteristics, teamwork behaviors and outcomes support the IPO model. The regulation of team performance mediated the effects of task meaningfulness and interdependence on team outcomes, with the direct effects of task meaningfulness on the preparation behaviors and the direct effects of interdependence on the task-related collaborative behaviors. The management of team maintenance mediated the effects of autonomy on team cohesion and satisfaction. The regulation of team performance has a direct effect on the team performance and the management of team maintenance. And the management of team maintenance has a direct effect on the team attitude and the regulation of team performance.