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1.
To convey the dynamic information related to traffic conditions in various parts of a city, we propose an environment utilizing the technology of smart phones to provide information anywhere and anytime. Called ";The Interactive Traffic Beat Project,"; it uses a Web-based service to deliver this information to people through their cell phones at the right time so that valuable time can be saved and the chaos on the roads can be managed.  相似文献   
2.
Building owners are increasingly interested in a healthy and sustainable living environment, which is a trend favoring ecological building materials with outstanding structural physical parameters. Insulation boards from particles of larch bark (Larix decidua Mill.) bonded with a formaldehyde-free tannin resin were pressed and evaluated for their mechanical and physical properties. It could be shown that light (target density 250 kg/m3) boards can be pressed, and their thermal conductivity is low (0.065–0.09 W/(m*K)). With regard to mechanical characteristics, the influence of panel density was studied, and it was found that a certain compaction (ρ ≥ 400 kg/m3) is necessary to meet the requirements of the relevant standard. Interestingly, the resin amount did not influence the mechanical board properties as strongly as expected, and panel density is the most important variable in this respect. The study proved that tree bark cannot only be used for substantially upgraded insulation panels but can also be bonded with a formaldehyde free tannin resin.  相似文献   
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以鸡胸肉为研究对象,在不同煮制时间下制备鸡汤样品,考察不同煮制时间对鸡汤中呈味物质的影响。采用高效液相色谱仪和氨基酸自动分析仪分析样品中有机酸、呈味核苷酸、游离氨基酸、呈味肽等的含量。感官评价结果表明,煮制4 h的鸡汤鲜味评分最高;随着煮制时间的延长,鸡汤的pH先降低后增加,煮制3 h时pH达到最低值(6.39);5'-胞苷酸(5'-CMP)、5'-鸟苷酸(5'-GMP)、乳酸和17种氨基酸的含量随煮制时间延长逐渐增加,在煮制5 h时达到最大值;5'-肌苷酸(5'-IMP)、和5'-腺苷酸(5'-AMP)的质量浓度分别在煮制2和3h达到最大值(14.22和48.72mg/L);琥珀酸的含量变化不大,谷氨酸的质量浓度在煮制5 h时达到最大值(291.39 mg/L),这些呈味物质对鸡汤鲜味具有重要的贡献。鸡汤的味精当量值(EUC)在5 h达到最高值(0.28 g MSG/100 g)。多肽含量在4 h时达到最大值(12.06 g/L)。  相似文献   
5.
T.S. Sonda    R.J. Kain    H. Yao 《Journal of food science》2002,67(5):1682-1687
ABSTRACT: Yield, gelation, viscosity, emulsifying properties, and sugar composition of polysaccharides extracted from tofu processing wastewater under acidic conditions at different temperature levels and incubation times were determined. Optimum extraction for water-soluble polysaccharides was at pH 1.5 and 100 °C over an incubation period of 6 hours. Extraction ratio (%) and yield of high-molecular-weight polysaccharides were higher at pH ranges of 1.5 to 3.0 with extraction temperatures of 80 to 100 °C. Most water-soluble polysaccharides extracted under strong acidic conditions and above 80 °C remained fluid, while most extracted within the range of 45 to 80 °C gelled. Pure polysaccharides exhibited better emulsifying properties than water-soluble polysaccharides. Apparent viscosities of water-soluble polysaccharides were dependent on sugar concentration.  相似文献   
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Sponging and excising were evaluated as sampling procedures for microbiological analysis of beef-carcass tissue. Brisket tissue portions (10 x 10 cm) were inoculated with 2 ml of an Escherichia coli ATCC 25922 cell suspension (3 x 10(8)CFU/ ml). After 30 min, the portions were sampled by excising (EX) or swabbing (SP) with a sterile sponge and were analyzed for aerobic plate counts on tryptic soy agar and for total coliform counts and E. coli counts on Petrifilm E. coli count plates. Another set of inoculated samples was analyzed after being spray washed, in sequence, with water (6 s, 35 degrees C, 3.4 bar), acetic acid (2%, 6 s, 35 degrees C, 2.1 bar), water (20 s, 42 degrees C, 20.7 bar), and acetic acid (2%, 6 s, 35 degrees C, 2.1 bar). Additional samples were sampled for analysis after chilling at 7 degrees C for 24 h. Bacterial counts recovered were influenced (P < or = 0.05) by procedure of sampling (EX versus SP), time of sampling (0.5 versus 24 h), and by their interactions. Counts recovered 0.5 h after inoculation from unwashed or spray-washed samples were similar between the two sampling procedures (EX and SP). However, counts recovered after 24 h of sample storage were significantly (P < or = 0.05) lower for the SP compared with the EX procedure. The results indicated that as the carcass tissue was stored, recovery of bacteria by SP was less efficient than was recovery by EX.  相似文献   
7.
High cycle fatigue tests in vacuum have been performed on ordered (Fe, Co, Ni)3V alloys between 25 °C and 850 °C. Heat-to-heat variations in fatigue properties of a Co-16.5 wtpct Fe-25 pct alloy, LRO-1, appeared to be due to differing quantities of grain boundary precipitates. Modification of this alloy with 0.4 pct Ti, to produce an alloy designated LRO-23, reduced the density of grain boundary precipitates and increased ductility, resulting in superior fatigue strength at high temperatures. The fatigue lives of LRO-1 and LRO-23 decreased rapidly above 650 °C, and increased intergranular failure was noted. The fatigue resistance of a cobalt-free alloy, Fe-29 pct Ni-22 pct V-0.4 pct Ti (LRO-37), was examined at 25 °C, 400 °C, and 600 °C; there was little evidence for intergranular fracture at any of these temperatures. Fatigue behavior of the LRO alloys is compared to that of conventional high temperature alloys.  相似文献   
8.
This article describes the corrosion behavior of special austenitic alloys for waste management applications. The special stainless steels have controlled levels of alloying and impurity elements and inclusion levels. It is shown that “active” inclusions and segregation of chromium along flow lines accelerated IGC of nonsensitized stainless steels. Concentration of Cr+6 ions in the grooves of dissolved inclusions increased the potential to the transpassive region of the material, leading to accelerated attack. It is shown that a combination of cold working and controlled solution annealing resulted in a microstructure that resisted corrosion even after a sensitization heat treatment. This imparted extra resistance to corrosion by increasing the fraction of “random” grain boundaries above a threshold value. Randomization of grain boundaries made the stainless steels resistant to sensitization, IGC, and intergranular stress corrosion cracking (IGSCC) in even hot chloride environments. The increased corrosion resistance has been attributed to connectivity of random grain boundaries. The reaction mechanism between the molten glass and the material for process pot, alloy 690, during the vitrification process has been shown to result in depletion of chromium from the reacting surfaces. A comparison is drawn between the electrochemical behavior of alloys 33 and 22 in 1 M HCl at 65 °C. It is shown that a secondary phase formed during welding of alloy 33 impaired corrosion properties in the HCl environment. This article is based on a presentation made in the symposium “Effect of Processing on Materials Properties for Nuclear Waste Disposition,” November 10–11, 2003, at the TMS Fall meeting in Chicago, Illinois, under the joint auspices of the TMS Corrosion and Environmental Effects and Nuclear Materials Committees.  相似文献   
9.
The purpose of this study was to evaluate a set of teaching materials on food, nutrition and agriculture, adapted at the Institute of Nutrition and Food Technology (INTA), University of Chile, within the scope of a project with AID and the School of Agronomy of the Chilean Catholic University (U. C.) aimed at incorporating the teaching of human nutrition into the curriculum of Latin American agronomists. A one semester course (54 hours) was given to 22 students of the 7th semester of Agronomy and two Ecuatorian agronomists (with AID scholarships). A set of knowledge evaluation instruments was applied at the beginning and at the end of the course. A total of 83.3% of the students passed the final examination (with more than 75% of correct answers). The difference between the initial and final performance was highly significant (p less than 0.001). According to the students' and teachers' opinions, the general textbook and the teachers book contributed effectively to meet the learning objectives whereas the students handbook needed some modifications. In conclusion, the program is an important contribution to the education of agronomists in a new conception of their role in regard to improvement of the nutritional status and quality of life of the rural population. With a few minor modifications, a final version to be used in the countries of the Region, shall soon become available.  相似文献   
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