液压系统双泵合流技术探究

介绍了目前液压系统中广泛采用的合流技术,理论分析了现在应用最广的外啮合渐开线齿轮泵的流量脉动。通过Autom ation Stud io对某型地下铲运机液压系统的转向液压系统和工作液压系统的合流分析,提出了液压系统合流技术可以降低液压系统流量脉动,提高液压系统工作机构的速度稳定性,降低系统噪声,提高工作机构效率。文章还分析了合流技术设计与装配的基本要求。最后总结了液压系统合流技术的应用及优点。

朝鲜细菌战:美日细菌战技术和力量的合流

战后美国掩盖日本的细菌战犯罪,独占日本细菌战技术发展自己的细菌武器。朝鲜战争中,美国在日本细菌战技术基础上,利用原日本的细菌战人员和建于日本的细菌战基地,在朝鲜和中国东北实施大规模的细菌战。

柔性混流装配线在智能工厂中的研究与应用

汽车行业智能工厂的建设成为必然趋势,实现精益制造,满足智能化、高效率、高柔性的要求,设计具有承载与非承载车型混流生产的汽车制造车间。依据承载与非承载车型不同的工艺特性,运用自动分合流、智能物流等技术,设计了承载与非承载柔性混流装配的工艺方案,首先装配工艺相近的车体内饰共线装配,然后两种车型自动分流输送至各自的底盘线,分别完成装配工艺完全不同的底盘装配后,再自动合流共线进行底盘内饰和整车装配,并确保分、合流时的顺序完全一致。同时,导入QRQC质量停线管理、重保重要管理、力矩防呆管理,设备故障报警管理等系统,具有信息化程度高、生产效率高、质量稳定、生产成本低等特点,实现了车辆的智能化生产,对传统汽车装配工艺进行了技术创新。该项目的技术特点是可以满足小批量、多品种车型柔性化、定制化客户订单生产需求,真正实现智能化制造,打造智能工厂。

三齿轮微泵设计与微Logix齿轮的铣削加工

渐开线齿轮和单泵供油技术难以满足微型齿轮泵高均匀介质和低损耗的工作要求。Logix齿轮根切倾向小、易于设计成少齿数。双泵合流技术可实现流量补偿并降低流量脉动。设计了一种基于Logix齿形的三齿轮微泵结构,三齿轮泵排量仿真结果表明,基于Logix齿形的三齿轮微泵较二齿轮泵的流量脉动性能好,三齿轮泵的排量比二齿轮泵增加1倍,而排量变化幅度只有二齿轮泵的一半。计算确立了Logix齿轮的结构参数,制订了Logix齿轮的微铣削工艺,加工制造了基于Logix齿形的微齿轮泵。

徐工LW540F轮式装载机

徐工LW540F是徐工集团2003年初推出的新品,是通过大量的市场调研,消化、吸收国内的先进技术,自行开发的一种换代产品,具有更强的市场竞争力,是一种高品质低价位的产品,现对其作一简单介绍.

Fabricating multifunctional polymeric nanofilm capable of resisting corrosion and activating copper surface by electrochemical and hydrolysis-condensation approach

A multifunctional polymeric nanofilm of triazinedithiolsilane monosodium salt, which can resist corrosion and activatecopper surface concurrently, was prepared by galvanostatic technique and the following hydrolysis-condensation approach.Electrochemical tests were carried out to evaluate the resistant ability of nanofilm. The changes of functional groups atop thenanofilms were monitored with Fourier transform infrared spectroscopy （FT-IR） and contact angles （CA） simultaneously. Thechemical composition and the morphology of the polymeric nanofilm were investigated by X-ray photoelectron spectroscopy （XPS）and scanning electron microscope （SEM）, respectively. The results reveal that the preferentially developed disulfide units protect thecopper during the whole preparation process, and the subsequently hydrolyzed nanofilms without/with heating shape into newinterface phases bearing the multifunctionality. This multifunctional interface （the polymeric nanofilm on copper surface） opens upthe possibilities for other OH-containing reagents to be anchored onto copper surface in demanding researches or industrialapplications.

Structure Characterization of Fluorosilicone Oils

Fluorosilicone oil is polysiloxane with alkyl side chains containing fluorine, and because of its excellent thermal oxidation stability, cold flow property and cryogenic property, it can be widely used as a high temperature lubricant in the field of military aerospace industry. Two kinds of fluorosilicone oils, FSiO-a and FSiO-b, were synthesized by different pro- cessing means. FTICR MS was used to collect the information on composition and structure of the two polymers, respec- tively. The test results show that the two fluorosilicone oils have different contents of fluorine-containing chain segments (m/ n value), the maximum distribution of m/n value of FSiO-a oil ranges from 0.22 to 0.25, and that of FSiO-b oil ranges from 0.4 to 0.67. Difference in synthesis techniques makes this discrepancy and affects the quality and thermal stability of the fluoro- silicone oils.

Numerical Modeling of Floating Oil Boom Motions in Wave-Current Coupling Conditions

Containment booms are commonly used in collecting and containing spilled oil on the sea surface and in protecting specific sea areas against oil slick spreading.In the present study,a numerical model is proposed based on the N-S equations in a mesh frame.The proposed model tracks the outline of the floating boom in motion by using the fractional area/volume obstacle representation technique.The boom motion is then simulated by the technique of general moving object.The simulated results of the rigid oil boom motions are validated against the experimental results.Then,the failure mechanism of the boom is investigated through numerical experiments.Based on the numerical results,the effects of boom parameters and dynamic factors on the oil containment performance are also assessed.

Degradation of Wastewater Containing Nitrobenzene by High Gravity-Ultrasonic/Ozonation/Electrolysis Technology

The integrated high gravity-ultrasonic/ozonation/electrolysis technology was applied in the pretreatment of wastewater containing nitrobenzene. The effect ofpH value, high gravity factor, liquid flow-rate and electric current density on removal of COD and nitrobenzene compounds was investigated. Experimental results have determined the optimal pro- cess regime involving a high gravity factor of 100, an electric current density of 20 mA/cm2, a liquid flow-rate of 100 L/h, and an initial liquid pH value of 11. After the wastewater had been treated for 180 rain, the degradation of nitrobenzene and COD reached 99% and 80%, respectively, with the biochemical coefficient （BOD/COD） equating to 0.64, and the subse- quent treatment of wastewater could be carried out by conventional biochemical means. Compared with traditional aeration- ozone contactors, a rotating packed bed with high mass transfer characteristics could be used to increase the ozonation treat- ment efficiency.

Research on thermode of operation of wisdom Logistics in large data background

With the rapid development of China＇ s economy and the accelerating pace of economic globalization, the rapid expansion of trade appears in goods, materials; space to move also will expand in breadth and depth, and thus the efficiency of the logistics activities, rapid response capabilities and the level of information logistics put forward higher requirements. Meanwhile, the logistics needs of personalization, diversification and sophistication, require that logistics service companies must constantly improve and optimize enterprise business model, and target to develop new logistics services to adapt to changes in the logistics market, and improve the competitiveness of enterprises.Modem logistics enterprises refer to the concept of modem logistics as a guide, and the use of modem logistics and organization of modem logistics technology, it is to provide customers help and reduce logistics costs and improve the level of integrated logistics services to rationalize logistics enterprises. Modem logistics enterprises are in terms of philosophy, mode of operation, services, information technology degree, logistics technology, enterprise systems and others have higher requirements to react quickly, service serialization, standardization of operations, the target of systematic, modem means are the features of the organization which are different from the traditional network of logistics enterprises.

Aviation

Aviation Industry Sub-council,a branch of China Council for the Promotion of International Trade(CCPIT),fulfils its mission under the guidance of CCPIT.Aimed at pro- noting export and import of aviation and

Cell proliferation of esophageal squamous epithelium in erosive and non-erosive reflux disease

AIM： To elucidate cell proliferation in erosive reflux disease （ERD） and non-erosive reflux disease （NERD）, we evaluated markers in squamous epithelial cells.METHODS： Thirty-four consecutive patients with gas- troesophageal-reflux-disease-related symptoms （21 NERD and 13 ERD） were evaluated for the enrolment into the study. All patients underwent 24-h pH moni- toring, standard endoscopy, and biopsy for histological evaluation. The expression of cyclins D and A was eval- uated by real-time reverse transcription polymerase chain reaction （RT-PCR） from isolated epithelial cells. In all samples, analysis of the isolated cell population revealed the presence of epithelial cells only.RESULTS： Real-time RT-PCR showed that, in patientswith ERD, the relative expression of cyclin D1 mRNA in esophageal epithelium was strongly decreased in comparison with NERD patients. The mean value of relative expression of cyclin D1 mRNA in NERD patients was 3.44 ± 1.9, whereas in ERD patients, it was 1.32 ± 0.87 （P = 0.011）. Real-time RT-PCR showed that, in patients with ERD, relative expression of cyclin A mRNA in esophageal epithelium was decreased in comparison with that in NERD patients （2.31 ± 2.87 vs 0.66 ± 1.11）. The mean bromodeoxyuridine labeling index in the NERD patients was 5.42% ± 1.68%, whereas in ERD patients, it was 4.3% ± 1.59%.

Remote Sensing Education for Life Long Learning across the East Midlands Region

Over the last decade, remote sensing technologies have provided useful tools for a diverse range of sectors. G-STEP （GMES--space technology exchange partnership） is the University of Leicester＇s flagship project for innovation, training and education in GMES （global monitoring for environment and security） and GIS （geographical information systems） based technologies. G-STEP （part funded by the ERDF） is the first GMES accelerator initiative in the UK and is breaking new ground in the application of GMES and GIS. The core G-STEP team initiates and develops Knowledge Exchange Practices between the University and Life Long Learning partners in the East Midlands Region, through training packages and collaborative research projects. The programme integrates innovative research, to direct downstream applied training, supported by analytical processing of attendee assessment data. Collated information derived from these sources presents a unique opportunity to incorporate a statistically viable feedback cycle, making G-STEP the interface between pure and applied research, thus initiating downstream dissemination to groups and small business. In this paper, we outline the GMES and GIS training packages, and the route to market to increase uptake of underused data streams via university and regional entrepreneurs （start-ups） and established small business with a core interest in utilisation and dissemination of novel technologies in sustainable lifelong learning.

Performance Enhancement and Utility Maximization for TCP in Wireless Mesh Networks

In Wireless Mesh Networks (WMNs),the performance of conventional TCP significantly deteriorates due to the unreliable wireless channel.To enhance TCP performance in WMNs,TCP/LT is proposed in this paper.It introduces fountain codes into packet reorganization in the protocol stack of mesh gateways and mesh clients.Furthermore,it is compatible with conventional TCP.Regarded as a Performance Enhancement Proxies (PEP),a mesh gateway buffers TCP packets into several blocks.It simultaneously processes them by using fountain encoders and then sends them to mesh clients.Apart from the improvement of the throughput of a unitary TCP flow,the entire network utility maximization can also be ensured by adjusting the scale of coding blocks for each TCP flow adaptively.Simulations show that TCP/LT presents high throughput gains over single TCP in lossy links of WMNs while preserving the fairness for multiple TCPs.As losses increase,the transmission delay of TCP/LT experiences a slow linear growth in contrast to the exponential growth of TCP.

Research on Resources Integration of the Fourth Party Logistics based on Multiple Agent

The key of the effective operation for the fourth party logistics is to integrate logistics resources with supply chain management concept and technology. According to the essence of the fourth party logistics resources integration, understand the characteristics of complexi .ty, the virtual and dynamic and so on, the paper analyzed the three kinds of Agent attribute for fourth party logistics resources integration system using the Agent technology and the principle, and then puts forward the fourth party logistics resources integration model of based on multi Agent.

A Contraction-expansion Helical Mixer in the Laminar Regime

A contraction-expansion helical mixer which combines several features, viz. helical pipes for induction of secondary flows and sudden expansion and contraction array tor expansion vortices, has been designed to en- hance flow mixing. A fast competitive-consecutive diazo coupling reaction is used to test the mixing efficiency of contraction-expansion helical mixer. Furthermore, an image processing technique is applied for data visualization and monitoring the extent of mixing. The mixing performance is found to be superior in comparison to the regular helical mixer in the range of Reynolds number from 170 to 1540. Moreover, the mixing time of contraction-expansion helical mixer was found to be reduced by more than 25% compared to the regular helical pipe. Finally, a simple correlation is proposed for predicting the mixing time.

Novel PLA/Chitosan Composite MaterialsPrepared by SCF-CO_(2) Technique

Because of the incomparable merits （nontoxicity, non-remainder, fast transfer mass） of supercritical carbon dioxide fluid technique（SC-CO2）, it was used to developed a series of novel biodegradable tissue engineering scaffold materials in this research. The novel PLA/chitosan composite materials could be molded to different shapes, and the porosity of the materials were over 200 lam and connected. Chondrocyte cultivation, subcutaneous and intramuscular implantation were mainly discussed this paper. The results showed that the cells could well adhere, grow and multiplicate on the surface of the materials, which indicated good biocompatibility of the composite materials. The plantation test revealed that the PLA materials had already dismissed 2 month late in the body, while the composite materials could still keep certain strength and shape, and the most important things is the response of the tissue toward the implanted PLA/chitosan composite materials was mild and had far less inflammation than PLA materials. 8 to 16 weeks later, fiber membrane was stable; degradation of the materials was seen clear and tissue had already spread into it.

托举的精彩 山推SL80W装载机

山推涉足装载机才不过几年的时间，目前已形成了载重2～8t的产品型谱。2012年，山推装载机在逆势中销量仍实现了45％左右的增长，对于一个后进入者来说表现出了快速成长的潜力。

Liquid metal-integrated ultra-elastic conductive microfibers from microfluidics for wearable electronics

Liquid metal(LM) has shown potential values in different areas. Attempts to implement LM are tending to develop new functions and make it versatile to improve its performance for practical applications.Here, we present an unprecedented LM-integrated ultra-elastic microfiber with distinctive features for wearable electronics. The microfiber with a polyurethane shell and an LM core was continuously generated by using a sequenced microfluidic spinning and injection method. Due to the precise fluid manipulation of microfluidics, the resultant microfiber could be tailored with tunable morphologies and responsive conductivities. We have demonstrated that the microfiber could act as dynamic force sensor and motion indicator when it was embedded into elastic films. In addition, the values of the LMintegrated ultra-elastic microfiber on energy conversions such as electro-magnetic or electro-thermal conversions have also been realized. These features indicate that LM-integrated microfiber will open up new frontiers in LM-integrated materials and the wearable electronics field.

Semiconductor nanowires for photovoltaic and photoelectrochemical energy conversion

Semiconductor nanowires （NW） possess several beneficial properties for efficient conversion of solar energy into electricity and chemical energy. Due to their efficient absorption of light, short distances for minority carriers to travel, high surface-to-volume ratios, and the availability of scalable synthesis methods, they provide a pathway to address the low cost-to-power requirements for widescale adaptation of solar energy conversion technologies. Here we highlight recent progress in our group towards implementation of NW components as photovoltaic and photoelectrochemical energy conversion devices. An emphasis is placed on the unique properties of these one-dimensional （1D） structures, which enable the use of abundant, low-cost materials and improved energy conversion efficiency compared to bulk devices.