KL-15型制氧制氮车的启封操作

<正>不少KL-15制氧制氮车的用户,对该设备首次启封心中无底。启封方法五花八门,有的甚至因启封不好而影响成套机组的运行性能。造成上述现象的主要原因,首先是因新设备启封只有一次,有关部门重视程度不够;其次,随着科学技术的发展,产品的结构、形式作了部分改进,启封技术指导滞后。笔者根据工厂多年生产状况及用户所出现的问题,就该型机组如何启封分三个阶段谈谈自己的看法。     

制充氮封存包装一体化设备研制

针对军用光电器材封存包装特点和应急保障需求,研制了军用光电器材制充氮封存包装一体化设备。介绍了制氮原理、工艺流程以及设备组成、功能特点等。大量的实践应用表明：设备运行可靠、性能优越,可现场对军用光电器材实施制充氮封存包装,实现军用光电器材的长效封存与快速启封。     

制氮设备采用外引气源维持运行

介绍了因空压机故障采用外引低压气源维持KDN 1 0 0 0型制氮设备低负荷运行的情况。详细分析了低负荷运行时需解决的“瓶颈”以及供风系统和空分系统的具体操作 ,对制氮设备正常运行与低负荷运行的参数进行了比较 ,最后介绍了低负荷运行操作时的安全事项     

43000m~3/h空分设备制氩系统的调试及操作优化

详细叙述兴化43000 m3/h空分设备制氩系统的调试过程。根据空分设备运行数据,结合其内在设计结构,采用边调试、边分析、边优化的方法,完成了制氩系统的调试,并提出了从设计上需对空分设备采取的改进措施。     

加氢制氩与无氢制氩流程结合制取纯氩的实践

酒钢动力厂6000m^3／h空分设备制氩系统采用加氢制氩流程，将经过粗氩压缩机压缩、冷却并干燥后的粗氩气，引入到21000m^3／h空分设备的全精馏无氢制氩系统中，实现了对加氢制氩流程的改造，有效地减少了设备操作和维护成本，并且停运了制氢站，获得了较好的经济效益和社会效益。     

加氢制氩与无氢制氩流程结合制取纯氩的实践

酒钢动力厂6000m3/h空分设备制氩系统采用加氢制氩流程,将经过粗氩压缩机压缩、冷却并干燥后的粗氩气,引入到21000m3/h空分设备的全精馏无氢制氩系统中,实现了对加氢制氩流程的改造,有效地减少了设备操作和维护成本,并且停运了制氢站,获得了较好的经济效益和社会效益。     

舞钢10000m^3／h空分设备短期停车后制氩系统快速恢复的操作

简介了舞钢10000m^3／h空分设备的主要技术参数和制氩系统流程，详细介绍了短期停车时和再启动时空分设备主塔、粗氩塔和精氩塔的优化操作。采取优化操作后，空分设备短期停车再启动时制氩系统恢复到正常工况仅需8-10b。     

舞钢10000m~3/h空分设备短期停车后制氩系统快速恢复的操作

简介了舞钢10000m3/h空分设备的主要技术参数和制氩系统流程,详细介绍了短期停车时和再启动时空分设备主塔、粗氩塔和精氩塔的优化操作。采取优化操作后,空分设备短期停车再启动时制氩系统恢复到正常工况仅需8~10h。     

实施设备点检制 减少设备故障

本文主要介绍了设备现状、实施设备点检制内容和效益。     

KL-15A型制氧制氮车的研制

简述了KL 15A型制氧制氮车的设计方案、设备布局、试验和试用情况 ;分析了此制氧制氮车的工艺流程及气氧、液氧、气氮和液氮四种工况的实现 ;并与KL 15型制氧制氮车的性能指标进行了简单比较 ;最后介绍了KL - 15A型制氧制氮车具有的技术特点     

套袋对梨和苹果采后果皮褐变的影响

目的 综述套袋对梨和苹果采后果皮褐变的影响,为解决套袋果实果皮产生褐变的问题提供一定的理论依据,最终使套袋果实的品质和商品价值进一步得到提高。方法 主要概括果皮褐变与其色素含量、相关酶活性、钙含量、酚类物质含量、果皮结构和膜脂过氧化程度等之间的关系。结果 不同果实、同一果实的不同品种、不同的套袋类型等因素都会影响果皮发生褐变的程度,套袋果摘袋后较未套袋果更易发生褐变的根本机制未有定论。结论 今后应加大对套袋果摘袋后果皮褐变发病机制的系统探究,明确褐变发病机理,将有助于防范和控制褐变的发生。     

Manipulation of individual double-walled carbon nanotubes packed in a casing shell

Controlled placement of carbon nanotubes is important for carbon-based nanodevice assembly. However, it is difficult to manipulate individual nanotubes because of their extremely small dimensions. Ultra-fine tubes are often in the form of bundles and are hard to efficiently move on a surface due to the strong adhesion among themselves and between the tubes and the substrate. This paper presents a novel manipulation approach of individual double-walled carbon nanotubes encased in a thick amorphous carbon shell. With an atomic force microscope, we are able to freely displace the nanotubes within a casing shell, and unpack it from the shell on a silicon surface. The theoretical analysis demonstrates that the unpacking process is determined by the difference of the static friction between the shell and the substrate and the resistance force between the shell and the embedded nanotube.     

镀陶烟用内衬纸防潮保润保香性研究

目的 研究对比陶制直镀内衬纸与常规直镀内衬纸的防潮保润保香性能。方法 对镀陶和常规直镀内衬纸进行SEM,BET和透湿率及透氧率检测,并将2种内衬纸卷制的成品卷烟放置于高温高湿、干燥、常温常湿等条件下平衡85 d,随后对拆包不同时长的卷烟进行烟支含水率检测,同时采用静态顶空气相色谱-质谱联用仪测定卷烟滤棒及烟丝中香精的主要成分含量。结果 与常规直镀内衬纸相比,镀陶直镀内衬纸的表面致密性和比表面积明显较优,且其氧气透过率略小,水蒸气透过率较小。在高温高湿和干燥条件下,镀陶样品的烟支含水率与初始设计值较为接近;在常温常湿条件下,2种内衬纸包装的烟支含水率虽在拆包前30 h无明显区别,但在35 h后,常规直镀内衬纸包装的烟支含水率显著下降,不满足设计要求。结论 镀陶直镀内衬纸的防潮效果较好、保香效果较好、保润效果略好。镀陶烟用内衬纸的工艺还有待进一步调整,以进一步提高其防潮保香保香效果。     

A multi-item multi-packaging model to minimise cost of lost units,unpacking cost and CO2 emissions

This paper presents two multi-objective models that integrate packaging size and production scheduling problems for a flexible flow shop system. The main objective is to find the packaging size of finished product per item and the production schedule that would minimise cost of lost units, unpacking cost, inventory cost, earliness/tardiness penalties and kilograms of carbon dioxide emitted by resources operation. Since the complexity of the proposed models, a Pareto-based hybrid genetic algorithm (HGA) is also developed. A case study was developed to analyse the performance of both models using different instances. Numerical results indicate that the outperformance of one model over the other depends on the demand and the packaging size.     

盘香取放及焚香一体化的包装结构设计

目的 研究并解决盘香和香炉外出携带不便,以及盘香拆封后不易保存等问题.方法 通过对现有盘香包装的调研,基于盘香自身的形状和人们的使用习惯,分析盘香包装的新需求,运用三维设计软件,对盘香包装进行结构设计,得出一款盘香取放以及焚香一体化的包装.结果 该包装结构可将盘香取出后在三层盖的中间层进行焚香,实现了盘香取放和焚香的一体化,保证了剩余盘香的密封性.结论 该包装盒外出携带方便、可重复使用、绿色环保、实用性强,为盘香包装的设计研究提供新的设计思路.     

Cholesterol tethered bioresponsive polycation as a candidate for gene delivery

The efficient unpacking of viral protein shell gave the inspiration for the synthesized vectors. In this research, novel cholesterol tethered bioresponsive polyethylenimine (PEI) was specially designed via disulfide-containing cross-linker. The cholesterol lipid had proved to increase the permeability of gene vector through cell membrane. The acid–base titration indicated that the synthesized polycation possessed efficient proton sponge effect, which was suggested to increase endosomal release of pDNA complexes into the cytoplasm. The cholesterol tethered polycation could effectively induce DNA condensation and form spherical particles with diameter about 200 nm at N/P ratio of 10. At glutathione concentration of 3 mM, the polyplexes were unpacked due to the bioresponsive cleavage of the disulfide bonds. The in-vitro experiment indicated that the polyplexes showed efficient transfection efficiency to HEK293T cells. All the results indicated that the bioresponsive polycation could be served as an effective trigger to control the release of DNA at the intracellular environment. The novel bioresponsive polycation might have great potential in non-viral gene delivery research and application.     

Maintenance Scheduling for Multicomponent Equipment

The problem investigated is the scheduling of preventive and opportunistic maintenance or replacement for equipment with more than one component under conditions of positive failure costs and increasing failure rates for all components. Dynamic programming models are presented for determining optimal policies for two and three component equipment. The resulting optimal policies are compared to commonly used policies and the often substantial diseconomies of such policies are illustrated. The (n,N) policies are found to be near-optimal under a wide range of opportunistic/preventive maintenance costs and failure rates for two and three component equipment. An approach for developing simple (n,N) policies for many component equipment is suggested.     

Semiautomatic installation for testing ac ammeters and milliammeters

Conclusions The principle of two calibrators first applied in an equipment for testing high-precision ac voltmeters [1] can also be used in the equipment for testing ammeters. This principle serves to obtain a high precision with a high productivity.Despite its relative complexity this equipment proved to be adequately reliable in use. Specialized installations for testing voltmeters and ammeters are more economical than universal ones for a large amount of testing.The principles on which the design of the installations for testing audio-frequency instruments are based [1] can also be used for constructing efficient high-frequency test installations.Translated from Izmeritel'naya Tekhnika, No. 1, pp. 69–71, January, 1971.     

基于仿生结构的吸顶灯电商包装设计

目的 设计大型吸顶灯电商缓冲包装,改变家用吸顶灯电商包装防护能力不足以及结构形式单一的现状,提升消费者的购买体验和品牌价值。方法 使用瓦楞纸板替代EPE缓冲材料,构造“蜂窝正六边形”仿生缓冲结构,提出无盖式与罩盖式2种设计方案。结果 与原包装比较,2款瓦楞纸板缓冲包装的抗压强度分别提高了80.8%与111.2%,快速封拆结构赋予消费者一步操作即可取用产品的便利性,解决了原有包装材料的环境非友好性、用户体验差等问题。结论 2种方案均采用瓦楞纸板仿生缓冲结构设计,不仅提高了包装对灯具的保护性能,而且提升了包装开启的便利性,为大型易碎类商品的电商包装提供了可借鉴的解决方案。     

Probabilistic seismic demand model and fragility estimates for critical failure modes of un-anchored steel storage tanks in petroleum complexes

Estimation of seismic vulnerability of existing equipment in petroleum complexes, traditionally has been done by using general fragility curves which have been developed for a group of equipment without considering their physical specifications. Although these kinds of fragility are suitable for preparing emergency plans and governmental decision making, for the sake of seismic upgrading of existing facilities, specific equipment fragilities are needed. In this paper un-anchored steel storage tanks, which is among the most vulnerable equipment in petroleum facilities, are selected for a case study. Probabilistic demand models for Elephant Foot Buckling (EFB) and welding failure at the connection between the bottom plate and shell are developed based on FEM analytical data, and a Bayesian updating rule is used to assess the unknown demand model parameters. The approach properly accounts for both aleatory and epistemic uncertainties. Developed probabilistic demand models are used to estimate the fragility of critical failure modes of selected tanks and real world data. The approach can be applied for other failure modes and other equipment, as well.