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- Abstract：To study further the property of xylanases from Streptomyces, purification of a xylanase from Streptomyces cirratus D-10 was investigated. A xylanase, named XynB, was purified by stepwise ammonium sulphate precipitation (20%-50% saturation) and Q-sephrose FF ion exchange chromatography. After two-step treatment, ten-fold purification was obtained with 24.0% activity recovery. The purified XynB showed as a single protein band on SDS-PAGE that molecular weight of the enzyme was estimated to be 22.0 ku by SDS-PAGE, and belonged to one of lower molecular weight xylanases.Keywords：Streptomyces cirratus,xylanase,purification,ammonium sulphate precipitation,ion exchange chromatography2|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Extraction and determination of mass ratio of Indigo and Indirubin in Indigowoad root were studied. Indigo and Indirubin were scanned from 240 to 700*!nm. From the spectrogram we can see that the largest absorbing wavelength of Indigo and Indirubin was 601 and 531*!nm respectively. The best parameters of technology have been determined through single factor and orthogonal test on extracting indigo and Indirubin respectively, results showed that ethanol with a volume ratio of 75% was suitable solvent to extract Indigo and Indirubin and 4 hours was the proper time to extract Indigo and Indirubin. Through orthogonal test the best parameters of technology were obtained. The results are as the following: the herbal granularity is 40 eye, extraction time is 4*!h, ethanol with a volume ratio of 75%. On this condition, the extracting rate was up to 1.74%.Keywords：indigowoad root,indigo,indirubin,mass ratio,extraction,determine3|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Keywords：Scutellaria baicalensis Georgi,flavoniod compound,pharmacological effects,advance in research22|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The kinetic energy of raindrop plays an important role in surface erosion processes. Wind affects not only the raindrop terminal velocity, but also the directional tilt of the raindrops, by which the angle of raindrop impacting on the soil surface will be determined. Thus it shows great influence on splash erosion on sloping field. The part of raindrop kinetic energy vertical to sloping field will be regarded as a kind of prime mover for splash erosion. Based on the distribution of raindrop terminal velocity, the raindrop kinetic energy distribution function and its density function were developed. As a consequence, the distribution of average raindrop kinetic energy over sloping field was obtained through calculus which varied with wind velocity, slope gradient and slope aspect as well as raindrop density.Keywords：wind vector,raindrop kinetic energy,erosion on sloping field0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to acquire cotton yield information and build yield map, cotton yield monitor system PF3000 of AgLeader Corporation was analyzed and studied, harvest experiments were carried out. During harvesting, cotton flow sensor and speed sensor were calibrated, yield data were processed. The result show: for cotton flow sensor and speed sensor, measurement errors can be reduced by calibration; as a cotton picker is working in a complex environment, errors can be inevitably introduced into the yield data; after processing of these errors, the quality of the generated yield map was better than before.Keywords：cotton yield monitor system,flow sensor,error,yield map,0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to determine the separating cylinder number of the dielectric fluffy cottonseed separator, experiments of separating fluffy cottonseed by different times under different separating voltages were carried out by means of the dielectric seed separator with single cylinder. Tests of significance on the experimental data were made by means of t test method. The result showed that it is necessary for the dielectric fluffy cottonseed separator to equip with two separating cylinders, which can increase the separating effect significantly. Three separating cylinders will not result in the increase of separating efficient, what they bring about is high seed loss instead.Keywords：dielectric,separator,fluffy cottonseed,cylinder number0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The effects of 1-methylcyclopropene(1-MCP) on the quality of green asparagus after harvesting. The results showed that the reducing of the chlorophyll level, as well as protein and sugar content in green asparagus were significantly inhibited by 1-MCP treatment. The increase of lignin content was also inhibited by the same treatment. The commodity rate of green asparagus treated by 1-MCP was 88% after 3 days storage at the room temperature.Keywords：Green asparagus,1-MCP,ethylene,postharvest quality,storage0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Keywords：up ventilation,greenhouse cooling,temperature,saving energy1|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Keywords：mechanical ventilation,greenhouse,solar radiation,computational fluid dynamics1|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To clarify the significance of study on the processing properties of straw materials, the status of the processing properties of straw materials and processing method and related machine were outlined based on experiments and analysis of literature. The development of compression and shear and tensile of straw materials were presented. The effects of processing method and cutting speed on the processing properties of straw materials were discussed. At present the main problems in this research field include three parts, system of testing and controlling can not fit the processing, research on quantify and status of processing are both limited. It is useful and important to research the straw materials properties of mechanics on impact load, to analyze its processing by FEM.Keywords：straw,processing properties,present status,problem,prospects1|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to measure the vertical jump height of human body conveniently and accurately, the method of indirect measuring was put forward. The state of motion during vertical jump of human body was analyzed theoretically. The measuring results showed that the indirect measuring of using photosensor is more accurate.Keywords：Vertical jump height of human body,indirect measuring,photosensor,3|5|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To improve the design of tank driving cabin and change the current bad match condition of its human-machine interface, an overall research of tank driving cabin human-machine interface evaluation should be taken on. Body-size of drivers, structure and position of components as well as the optimum area, general area and function-limited area of each component, which are determined by the performances of the components, were considered as the main factors during evaluation. Based on the System-analysis and Ergonomics principles, the human-machine Interface of tank driving cabin is divided into 6 parts: manipulated space, diver's seat, some important controls, periscope, instrument panel and other controls. The evaluation factors were selected and the evaluation items and levels of the human-machine interface were described specially. All of these form the evaluation system of human-machine interface of tank driving cabin.Keywords：tank driving cabin,human-machine interface,evaluation factors0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Keywords：the small separated heat pipes,heat exchanging,liquid ratio,2|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The development process of electronic control technique of diesel engines was reviewed. The proportional-integral-differential principles of the position electronic controlled is discussed. To feature of BF8L413F diesel engine and BOSCH-P8AE pump. The effects influcing the diesels' oil temperature & input air pressure were analysed. The diesels controlled system by adding pressure sensor and temperature sensor to improve BOSCH-P8AE pump properties and adaptabilities were discussed. Bench test for MC68376-based BF8L413F diesel with this electronic control system was carried out. The results of test showed that the properties of this system is better and this system has some application worthiness.Keywords：diesel engine,electric control,MC68376,PID0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to solve the problem of which the working characteristics can not be tested directly, a new method of testing working characteristics of three-phase induction motor on line on the base of theory of round chart was developed. This system was realized by 80C51 technology. It use chip 80C552 as CPU and is composed of sampling and holding, filter wave, display and print circuits other than the system of 80C552. The software is compiled by C51. The results of the new experimentations was compared with the results of traditional experimentations at the same condition and the error was within the confines of Chinese standard. It has been proved that this new method was credible and convenient.Keywords：three-phase induction motor,testing on line,working characteristics,theory of round chart0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：A selection method on threshold and threshold function which are used in engineering drawings denoising based on orthogonal wavelet packets transformation was discussed. The corresponding procedure was proposed. The testing result showed that the method proposed on this paper was reasonable, and the selections on threshold and threshold function was reasonable and feasible.Keywords：wavelet packets transformation,engineering drawings denoising,the selection of threshold,the threshold function0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：A scheme to construct an e-business platform for medium and small chained stores was proposed. The 3-tier application model B/W/D was chosen as the website's structure model, by which the separation of the application server and the database server can be realized. The opened resource combination of Linux+Apache+MySQL+PHP has been reduced the website cost, which would attract the interest of most medium and small enterprises.Keywords：3-tier application,PHP,LAMP,MVC mode4|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：It is the tendency of the development of the software that using OO technology to design and develop the applied software. In order to establish the object-oriented system model of blanking dies of CAD/CAM on the VB platform, it is essential to use the inheritance which is supplied by the platform. But VB does not supply the realizing inheritance directly. Although it supports multi-morphology it has to run in low efficiency. In fact, these problems can be resolved when making use of the interface technology. The inheritance can be realized through realizing interface inheritance, and the multi-morphology can be improved. Using this technology and GUIDS method, it becomes reality to establish OO _based system. At last, the comparative scientific system model which making the part to be the base class was established, and through realizing this model, system realized the OO completely. At the same time, the maintenance and expansion of the application software were strengthened.Keywords：object-oriented,class,interface,blanking dies,CAD/CAM,GUIDS,OO,OOD,OOP,0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Some factors that influence innovative capability of the technology human resource was studied from many aspects, evaluating index systems of technology human resources was developed in order to increase the level of creative capacity of the high-tech. Adopting misty and synthetic evaluation method, at the same time, adopting compare research between enterprises, inquiry and statistic methods, the evaluation analysis was carried out. The inquiry and statistic method colligates opinion of inner and outer clients, and an excellent enterprise is regarded as the model about the compare research between enterprises. As a result, people can truly and effectually know the actualities of the technology human resource, find out differences between enterprises and the reason, some gist and references were offered in order to increase the level of creative capacity of the high-tech of technology human resouces.Keywords：technology human resource,synthetic evaluation,evaluating index2|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
Fuzzy comprehensive evaluation of industrialized agribusiness selecting agricultural garden district
Abstract：According to a lot of outer factors, such as the natural environment, water and electricity supply. Communication conditions, the distance to the target market, transportation daily life service, the preferencial poticies from the government and the administration of the district, etc, the evaluation standards were developed, and each factor in the district was evaluated by the experts. The math model was built by the fuzzy math. The evaluation results were fuzzy comprehensive evaluated. The results were qualitatively processed. Finally, the comprehensive evaluation grade was obtained. The results of the case study showed that the enterprices can effectively select the garden district where will be good for the enterprice development.Keywords：factory agribusiness,agricultural garden,fuzzy comprehensive evaluation2|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27- Abstract：Fuzzy evaluation method was used in the taxis of the development level of the chain business in thirty districts and gained four clustering groups from the analysis of the taxis so as to facilitate the government to instruct the enterprises accordingly and to facilitate the enterprises to establish strategic program. The first group of chain business developed fast with highest standard and the most favorable environment; the second group mostly was located on the eastern coast of China which develop relatively fast with favorable environment; the third group mostly was located in the mid-west where needs the reformation, its development speed was rather slow with lower level and worst environment; the fourth group of chain business develop slow because of natural environment and social economic conditions. The research results conform to the actual condition. Great effort put in the further development of the chain stores of the first and second groups and more instruction and support devoted in the chain stores in the mid-west is the most realistic strategy in the further reform of the circulation mechanism in China, and is also an effective way of entering the international market for franchise trade.Keywords：fuzzy evaluation,clustering method,chains-business levels1|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
