High Efficiency Classification Technology Research for the High Quality Sn-Pb Powder

Powder technology is one of the most important Basic technology to support high-tech industrial. The classification technology of powder is important part of powder technology. The welding powder used by SMT technology has two traits including high specific gravity and high requirement of non-oxidizability that make classification hard for high quality Sn-Pb welding powder .But the turbine flow classifier used widely in industry can not be satisfied with the requirements of high quality Sn-Pb welding powder, it’s high speed rotating rotor makes heat motion intense. As a result , oxygen content of powder has been increased ,so the quality of production can not be guaranteed.In this paper the design scheme of new cyclone-type separator was presented according to such characters of Sn-Pb welding powder as high gravity and oxidizability and the theory of cyclone classification, the structure of conventional cyclone separator was improved, and new cyclone separator was developed. Through researches on three primary processing parameters such as the wind rate of blast airfan of cyclone separator、the second wind rate and particle flux thrashing structure, optimal processing parameters were obtained: ten holes for second wind rate、7.2mm aperture and frequency of blast airfan of 40HZ.Results show that compared with products obtained by turbine flow clarifier classifying Sn-Pb powder the grain size of clarified powder reached 25 um, and oxygen content dropped up 30ppm.Comparing to old process of factory , using new equipment of classification has decreased process , knocked down, improved quality of product a lot. In conclusion, the quality of product satisfied the requirements of clients.

Theory Shift and Institution Change: The Pedagogy in the Year from 1949 to 1956.

The paper takes the development of the pedagogy as the case, firstanalyzes the interaction relationship between the disciplinary institutionand the theory shift in the planned economy times,then reveals the socialconditions in the reality of the changes of the pedagogy knowledgemodel, on the purpose of understanding the disciplinary institution whichis based on the universities and colleges how to give support to the theoryshift, exploring the problems and the limitations which lies in thetheoretical innovation at present.The contents include the following:Introduction: the summary of the origins of this paper, the definitionof the concepts related, the explanation of the research Perspective andthe analytical frameworks and research methods.ChapterⅠ: the retrospection of main states of the pedagogy’sevolution before the founding of the people’s republic of China. firstrespectively describes the history state of Dewey’s pedagogy and Herbartpedagogy, then explains the reasons and the impact of them after they areintroduced into China, Finally analyzes the Basic conditions of thedisciplinary institution of the pedagogy before the founding of thepeople’s republic of China.ChapterⅡ: explanation the historical conditions and the process ofthe theory shift of the pedagogy in the years of the founding of thepeople’s republic of China. Describes the experiences and the fate whichDewey’s pedagogy encountered in the early years of the founding of thenew state, then discusses the introduction and the promotion of Kairovpedagogy in new China, Finally analyzes the substance of the theory shift of the pedagogy.ChapterⅢ: a study and analysis of the process of disciplinaryinstitution of the pedagogy which was at the core of profession in theearly years of the new state, explain the interaction relationship betweendisciplinary institution and the academic authority establishment ofKairov pedagogy. finally the paper shows the impact which thecentralized and planned disciplinary institution gives to the developmentand innovation of academic.Conclusions: based on the exploration and inspection of the theoryshift of the pedagogy and the changes of the disciplinary institution, itcomes to two conclusions,the first one is that the theory shift of thepedagogy is rapid and under the control of the political power. The shiftis obvious power-oriented. Second, the changes of disciplinary institutionof the pedagogy provide support to the theory shift. However, the planneddisciplinary institution plays restrictions to the academic innovation andacademic development.

Research on High Production, High Efficiency and Water-Saving Crop Rotation Systems in Shiyang River Area

Shiyang River Basin is the area with the longest history of irrigation,biggest population density, and highest utilization of water resources.While, sharpest contradiction between water demand and water supply was existed in this area,whichis the most serious Environmental problems in the northwest inland river basins and the water resources limited the economical development largely. So, watershortage become the bottleneck for Shiyang River Area’s development. Irrigation water consumption took up 86% in Shiyang River Area’s water resource, and the main plant model here was wheat-maize rotation. So, developingwater-saving irrigation is the most effective method to sovel the problem of watershortage, and by regulating the crop patternsl to save water will bacome the key piont field.The article was taken the city of Wuwei in Gansu province for reasearch area.Firstly, five plant models were chosed, which were used in Shiyang River commonly, and field irrigation experiment was adopted to study the water requirement and water requirement lawin order to give the suitable irrigation program in this area. Then, we carried out five rotation models for the five plant models at three different irrigation levels. The experiment started in March in 2008 and ended up in October in 2009.Comparative analysis method was usedin order to compare each cropping system about its yield, water consumption, WUE and Economic benefit.The main purpose of this study was to select one or more cropping patterns, which had the function of water saving capability and high efficiency to substitute the traditional wheat-maize rotation patterns. Finally, we exploratoryly chosed two rotation models, and compared their yield, water consumption, and Economic benefit with wheat and maize respectivelyin order to provide practical and theoretical basis for achievement the sustainable Agricultural development in Shiyang River Basin.The main results were as follows:(1) Five plant models’water requirement and water requirement law showed: Spring wheat, maize, oil-sunflower, wheat intercrop maize, wheat intercrop soybean’s water consumption is 480.5 mm, 569.0 mm, 291.0 mm, 636.4 mm, 571.6 mm, respectively. By comparison, wheat intercrop maize’s water consumption is the maximum, and oil-sunflower’s water consumption is the minimum. For the five plant models: the key irrigation period appeared in jointing and blooming stage for spring wheat, in jointing and silking stage for maize, in squaring and blooming stage for oil-sunflower, in jointing and blooming stage for wheat intercrop maize, in jointing and branching stage for wheat intercrop soybean, respectively. The suitable irrigation times for the five plant models were four, five, two, six and six times, respectively.(2) Five rotation model for the five plant model showed: the average yield (kg·hm-2) of five crop rotation indicated that: maize-wheat intercrop maize (18181) > seed oil sunflower-wheat intercrop soybean (14988) > wheat intercrop soybean-wheat (14763) > wheat intercrop maize-oil-sunflower(14652) > wheat-maize (12554, contrast); the average water consumption (mm) indicated that: maize-wheat intercrop maize (1091) > wheat intercrop maize-oil-sunflower (938) > wheat-maize (906, contrast) > wheat intercrop soybean-wheat (852) > oil-sunflower-wheat intercrop soybean (842); the average water use efficiency (WUE) (kg·hm-2·mm-1) indicated that: oil-sunflower-wheat intercrop soybean (17.9) > wheat intercrop soybean-wheat (17.2) > maize-wheat intercrop maize (16.5) > wheat intercrop maize-oil-sunflower (15.3) > wheat-maize (13.9, contrast); the average crop economic benefit(yuan·hm-2) indicated that: oil-sunflower-wheat intercrop soybean (43290) > wheat intercrop maize-oil-sunflower (29751) > maize-wheat intercrop maize (21129) > wheat intercrop soybean-wheat (18815) > wheat-maize (15790, contrast).Take the total yield, water consumption, WUE and economic benefit of different crop patterns into consideration integratedly, we conclude that oil-sunflower-wheat intercrop soybean and wheat intercrop soybean-wheat could alternate the traditional pattern to achieve sustainable Agricultural development in the Shiyang River Basin.(3) Two new rotation models showed: seed oilsunflower-winter rape’s irrigation is as same as maize, but if compared to wheat and maize respectively, its net income increased 33750 yuan·hm-2 and 28035 yuan·hm-2, water consumption increased 170 mm and 69 mm, and its conresponding irrigation efficiency increased 340% and 139%,.Seed watermelon-oilsunflower’s irrigation is as same as wheat, if compared to wheat and maize, net income increased 27705 yuan·hm-2 and 21990 yuan·hm-2, water consumption increased 6 mm and -95 mm, and irrigation efficiency increased 284% and 109%, respectively. The main principle of these two new rotation models was to use cash crops instead of food crops, and irrigation in different season instead of over-irrigation in summer. Thus, the two plant model optimized the plant struction, slighted the contridiction between water supply and water demand, saved resource and protected ecological environment, so as to guarantee the Shiyang River Basin’s sustainable development.

The Analysis on the Case about the Taste of Product

It’s said that rationalism has been popular for a century, should begun to focus on fun-oriented design now. Product design has been a fun attention. Product design in every stage of historical development, the design of each movement and the emergence of design will increase the focus on people to a new level, if we from the product point of view of human nature, including for people taste different understanding of the needs of, and achieved varying degrees of taste demands on people’s satisfaction. A taste of the human spirit needs, both emotional and generally associated with mass culture, but also with people’s real-life emotions resonate. Interesting is that people demand of a deeper emotional pursuit. China today in the Social, Economic, cultural and other areas have made great achievements. The rapid development of science and technology not only greatly expand the design content, but also more creative design activities, can be said that technology allows the design to become all things are possible. At the same time improve people’s spiritual needs, to meet the growing emphasis on individuality, the spirit of pleasure and delight of life improvement, emotional catharsis and self-focused self-realization. People’s lifestyles, spending patterns are gradually changing, increasingly showing a fun, fashion and personalization trend, the last of the “rational-led” into the current “driven by emotion,” Contemporary emphasis on emotional satisfaction society has entered the era of human nature. In this context, emotional design began to appear. As an industrial designer to quickly capture the times, the integration of design elements, change the design thinking, with a new perspective to the product development and design, to create more consistent with the requirements of the times full of fun-oriented products.Product design is a fun product-media, design and emotion to achieve harmony and unity, and thus create a more beautiful way of life, add life, fun atmosphere of the bar. It is no uniform definition, but rather with the Social needs of the spontaneous emergence of a design theory, this theory development is not yet mature, but it is need of the times, is the product of social development. Interesting design is the design theory of human consciousness on the basis of an extension into a new theory. This is mainly through a lot of reading and extensive research, etc., from a large social context of contemporary product design leads to interesting design concept, a series of fun at home and abroad of the products from the shape, color, materials, used and aesthetic function and other aspects of analysis, and finally put forward some interesting product design principles and methods to further improve the taste of rich design and user-friendly design theory.

A Study on Farmers in Underdeveloped Regions of Marriage Research Expenses

Since the 1980s, China has undergone tremendous changes in rural areas and shown the world the face of rapid Economic development, constantly improve the income of the farmers. At the same time, consumption of the peasants of marriage, and marriage customs have been a different understanding, but also makes the cost of the rural society of marriage, as well as the concept of marriage have taken place in consumption is not a small change. In this paper, in Gansu Province as an example of an ordinary village, the use of sociological methods of investigation such as interviews, this article will be engaged to marry into the cost of fees, “salute” the cost of the dowry, wedding four major components of expenditure. Of the village since 1981 and married in 2008 the situation changes in the cost of a description of changes in its reasons for a series of analysis, and use it as an entry point to the farmers in recent years of changes in consumption concept of marriage.By D survey of the village, this paper argues that rural areas in recent years is the rising cost of marriage, including such. The reason there are many objective and subjective, mainly due to the growth of the income of the farmers, the farmers of the changes in lifestyle, family size and patterns of rural change, marriage market, the shortage of resources for women, the psychological impact of competition. At the same time, changing the cost of that marriage, but also be able to dialysis to farmers the concept of marriage and spending some of the Basic features, see the positive side and the performance of somenon-rational. We found that the current cost farmers in the process of marriage are becoming more and more rational, a series of procedures to continue to simplify the marriage, the marriage is still the conclusion of the course by the traditional habits and the impact of traditional customs. At the same time, farmers also have the concept of marriage and the consumer does not conform to the reality of trying to imitate the local cities, and “face” issue has always been the highlight.

Effects of1-bromopropane Exposure on Cognitive Function in Rats and Its Mechanism

Objectves1-Bromopropane (1-BP) was recently introduced as an alternative cleaner to1,1,1-trichloroethane, chlorofluorocarbons and suspected carcinogens such as trichloroethylene, methylene chloride, which have the potential to destroy the ozone layer. The neurotoxic effects of this agent have been described in humans and experimental animals. It affected the function of the central nervous system and caused disorders of peripheral nerves. But its mechanism of neurotoxicity in humans is not well understood. In this study, the rats were treated with different dosage of1-BP by gavage, and the Morris water maze (MWM) test was applied to evaluate the learning-memory function in rats. After the MWM test, rats were sacrificed, the cerebral cortex and hippocampus quickly dissected and homogenized in ice bath. The supernatant of their homogenate was collected to detect the changes of the central cholinergic system and the oxidation and anti-oxidation system respectively. The aim of our study is to illustrate that the dysfunction of the central cholinergic system and the antioxidative system are attributed to the damage of cognitve function.MethodAfter3days acclimation,48Male Wistar rats were randomly divided into four groups with12in each, i.e.1-BP low-dose group (200mg/kg), medium-dose group (400mg/kg), high-dose group (800mg/kg) and control group. Animals in each group were given in accordance with their own dosage for7days, and then the Morris water maze (MWM) test was applied to evaluate the learning-memory function in rats. The escape latency, total distance in the place navigation trial, and the percentages of the time spent in the platform quadrant, the number of platform crossing in set time of spatial probe trial were recorded respectively.After the MWM test, rats were sacrificed, the cerebral cortex and hippocampus quickly dissected and homogenized in ice bath. The supernatant of their homogenate was collected to detect the activity of Acetylcholine esterase (AChE), Choline acetyltransferase (ChAT), Glutathione reductase (GR), Glutathione Peroxidase (GSH-PX) and the content of Glutathione (GSH), Malondialdehyde (MDA), Total Hydrosulfide (-SH) and Acetylcholine (ACh) both in Cortex and the hippocampus. The4-HNE and MDA ptotein adducts were both detected by western blotting.2of rats in each group were fixed in vivo with4%paraformaldehyde solution, and the rats’ brains were dissected. After paraffin embedding, serial sections were done at intervals of5μm. then, tissues sections were stained with hematoxylin-eosin to observe the structure of neuron in cortex and the hippocampus.Results1. The results of the MWMCompared with control group, the latency and total swim distance of rats in medium and high-dose groups were prolonged significantly (p<0.05) in place navigation test, the efficiency of searching strategy was lower (p<0.05) as well. In spatial probe test, the number of crossing the platform of rats in three dose groups decreased evidently (p<0.05,p<0.01). The cortical AChE activity of rats in medium and high-dose group was significantly higher than that of control and low-dose group (p<0.05,p<0.01). The AChE activity in rat hippocampus of high-dose group also increased (p<0.05).The cortical ChAT activity tended to decrease after treating1-BP but there was no statistically difference compared to the control group (p>0.05). In the hippocampus, there was no difference of ChAT activity among the groups (p>0.05). 2. The changes of Biochemical indicatorsIn our study, the cortical AChE and GSH-PX activity of rats in medium and high-dose group was higher than that of control and low-dose group (p<0.05). Also the activity of AChE was increased in the hippocampus (P<0.05), but there was no obvious difference in the four groups about ChAT. The contents of MDA in the cortex increased appearently (P<0.05,P<0.01). In addition, the contents of GSH, Total Hydrosulfide and the activity of GR all reduced significantly (P<0.05,P<0.01)3. Western Blotting resultsCompared to comtrol group, densitometric analysis showed that the express of4-HNE protein adducts in the brain of the three dose-groups increased by42%(p<0.05),44%and77%in the middle and high-group (p<0.01). The content of MDA modified proteins in the brain in the three dose-groups were all increased, but only the high-dose group had a significant change by an increment of86%(p<0.05).Conclusion1.1-BP exposure could significantly damage the learning-memory function in rats.2. The disfunction of the rats’learning and memory might be partly ascribed to the changes of the central cholinergic system induced by1-BP.3. The disturbance of oxidation and antioxidation system in rat’s brain might attribute to the injury of the cognitive function of rat exposure to1-BP.

Preparation of Nano-sized Gold Catalyst Au/La-Fe-O and Their Catalytic Performance for CO Oxidation

Supported gold catalysts are a new kind of catalytic materials and exhibite fine catalystic activity for variety reactions, including oxidation of low temperature of carbon monoxide and volatile organic compounds, water-gas shift and some other selective oxidation reaction. So the research on gold catalyst has been the focus due to the fine application potentials of industrial and Environmental protection. In recent years, more attentions have been paid to the new methods for the preparation of the gold catalysts with low gold loadings and high activity, especially the high stability.In this paper, a series oxides La-Fe-O were prepared by sol-gel method and the catalysts were prepared by deposition-precipitation(DP) method. The effects of the pH value、the gold loading、the calcination temperature and the supports to the catalytic performance for CO oxidation were investigated. Then these catalysts were characterized by means of XRD、BET、AAS、H2-TPR and FT-IR. The performance of catalysts derived from the oxides Fe2O3、the mixiture oxides La2O3+Fe2O3 and the perovskite oxides LaFeO3 were compared for CO oxidation. In order to improve the catalyst stability, Fe(OH)3 was added as well.The experiment results indicate that:(1) the support structure and the kind of support affected the catalytic performance. The catalysts derived from oxides Fe2O3 and the perovskite oxide LaFeO3 had batter catalytic activity than that derived from other supports. (2) The preparation condition had influence on the catalyst activity. The catalyst Au/LaFeO3 obtained at pH value of 7、the gold loading of 2% and the uncalcined catalysts exhibited high catalytic activity. CO was totally converted to CO2 at the temperature of 0℃. (3) The stability experimental indicated that the catalyst Au/LaFeO3 calcined at 100℃had better stability than that of uncalcined catalyst. The 170-days preserved catalysts revealed nearly same activity with the fresh catalysts, but the T100 of uncalcined catalyst increased from 0℃to 60℃. Furthermore, the stability of fresh catalysts was superior to that of 170-days preserved catalysts. Au/Fe(OH)3/LaFeO3 and Fe(OH)3/Au/LaFeO3 had better stability than Au/LaFeO3.Based on the characterization of XPS and FT-IR over the fresh and calcined catalyst, it was found that that oxidation state Auδ+(0<δ≤3) is the active species. The decrease of oxidation state Auδ+(0<δ≤3)、the accumulation of carbonate on the catalyst surface and the growth of the crystallite size of gold may be main reasons for deactivation of the catalyst.

Application Research on Key Technique of Video Processing Based on Hisense HS2501

With the development of technology and people’s increasing requirement, the digital system is being used in more and more fields, especially in the fields of vedio. The launch of VPE1X, which was the first generation video processing chip developed by Hisense, has made it a breakthrough. The second-generation chip, HS2501, has been launched this year. It is integrated additional functions and to optimize the processing technology.The key problems of technologies were studied in this thesis,which were involved in the design, development and application of the HS2501 and proposes reasonable solutions. The thesis is mainly composed of five parts: firstly, the vedio digital process system and its general developping method is introduced, and then the whole design scheme is brought forward using the concept of software-hardware codesign; secondly, the HS2501, which is of vedio kernel, is chosen as the kernel of hardware platform, which adopts the module-design method, and after other devices having been chosen out to meet the need of system parameter, the module circuit comes up; thirdly, the process of PCB design and hardware debugging are introduced and the key problems encountered in the procedure are discussed, as well as the corresponding solutions; following that is the picture improvement design, including the module debugging; after the hardware-software codesign and debugging, combined with the application, a method of applying the nonstandard signal is proposed. Summary is made at the end of the thesis and the further research direction is proposed.

With the development of technology and modern industrialization, env…

With the development of technology and modern industrialization, Environmental pollution problems become increasingly severe. In order to deal with avarieties of harmful substances, a variety of physical, chemical, biochemical and other methods of industrial production came into being generated, but most methods exist some shortcomings,for example long cycle, large Investment, and other degradation is not thorough enough. In1955, it marked the beginning of modern photochemical theory that Brattain and Garret found the phenomenon of photovoltaic germanium semiconductor electrodes.In1972, Fujishima discovered the N-type semiconductor TiO2could electrolysis water under the irradiation of in light, this phenomenon announced the arrival of the new millennium that use photoelectric catalytic method to solve the pollution problems.As we known the photocatalytic technology,simple to operate, easy to control, high efficient decomposition of pollutants, single equipment, has opened up the new research directions about the organic dye, biodegradable industrial wastewater Environmental pollutants.The first chapter describes in detail the physical and chemical properties of titanium dioxide, the Basic principle used as photocatalytic and improving the way of the photocatalytic titanium dioxide photocatalytic properties, and introduced the prospect of titanium dioxide in the Environmental field.The second chapter describes common methods for preparing TiO2films as well as the advantages and disadvantages of various of preparation methods, focusing on introduce the machine of this experiment RF magnetron sputtering. Characterization of the film as a simple introduction, and a detailed description of principle magnetron sputtering apparatus for preparing TiO2films and the decomposition principle of methyl orange.The third chapter describes the operating procedures for preparing TiO2thin films by magnetron sputtering apparatus, and a detailed description of the preparation of TiO2target and the experimental procedure TiO2films.The fourth chapter discusses the influence of substrate temperature and sputtering power of titanium dioxide thin film transistor structure and photocatalytic properties. The film samples detected crystal to change by XRD, By atomic force microscope to detect the film surface; Calculating the particle size change of the film surface roughness by the formula; The use of methyl orange decomposition under UV irradiation to illustrate the photocatalytic properties of the film.The fifth chapter focus on discusses the the difference effects of annealing temperature and the annealing time on the structure and photocatalytic properties of TiO2thin films. By UV-visible spectroscopy analysis its optical properties; Calculating the indirect band gap by extrapolation bandgap film samples; Through XRD detected the phase changes of crystalline thin film samples with increasing annealing time; Finally, through the atomic force microscope (AFM) to observe the morphology of the film surface.

A Comparative Study of the Chinese Political Development in 1980s and 1990s

Contemporary Chinese politics has undergone an arduous but important period since 1978. To find the inherent laws of contemporary Chinese politics, the thesis has a comparative study of the political development in 1980s and 1990s. By and large, the Chinese political development in 1990s has gone beyond the limit of Chinese political development in 1980s in some aspects, including the harmony of socialism and modernization, the improvement of the political authority’s rationalization, the perfection of political institution and the synthetical development of political democratization. Certainly, there are some problems in the Chinese political development in 1990s as well as in 1980s, the most important of which is the conflict between the centralization of power and the dispersal of power under the increase of the amount of power. In another words, the contradiction between the democracy and efficiency still exists. To systematically compare the political development in 1980s and 1990s is of great value of theory and practice .It fills the vacancy in the sphere to systematically explain the contemporary Chinese political development with the theory of political development. Furthermore, to systematically compare the political development in 1980s and 1990s provides the experiences and lessons for the political development in 21st. On the basis of these, the thesis boldly forecasts the objects and dynamics of political development in 21st.