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51.
Abstract A random sample of 450 houses representing various decades was surveyed by trained civil engineers for signs of water leaks or condensation. In 80% of the houses, signs of current or previous moisture fault were observed. In most houses, the surveyors made at least two separate observations of moisture but the occupants missed one in every two of these signs of moisture damage. Part of the faults were caused by flaws in design or construction, and part were due to aging of materials. Approximately 55% of the Finnish houses (i.e., a total of nearly 500 000 houses), were assessed to be in need of repair or more thorough inspection. The observations were equally frequent in the houses of different age, but certain types of moisture damage were characteristic of certain types of buildings or constructional methods used in different eras. Roof geometry was a significant factor accounting for roof leakages. The majority of the faults could be repaired at reasonable cost.  相似文献   
52.
The paper presents the results of study on polymorfisms of xenobiotic biotransformation enzymes (CYP1A1, glutathione S-transferase MI and N-acetyltransferase 2) and p53 tumor suppressor protein in patients with lung, stomach and intestine cancer. The frequency of CYP1A1-Val allele in all studied cancer groups was 3 to 5 times higher than in healthy control group. The carriers of homozygous glutathione S-transferase M1 gene deletion and slow acetylator phenotype were also of higher lung cancer risk. The substantial increase in slow acetylator phenotype frequency was shown also in the group of intestine cancer patients. The p53 Arg/Pro polymorphism study revealed the elevated frequency of Arg allele in lung and stomach cancer groups. The risk of lung cancer for the carriers of susceptible alleles depended on the age and smoking status of the patients. The results testify to a high possibility of studied polymorphic genes to be the markers of susceptibility to oncopathologies.  相似文献   
53.
In this paper, parallel distributed detection in wireless sensor network (WSN) is investigated. Sensors are assumed to be transmitting their local decisions to a fusion center through a wireless fading channel using cooperative transmission. To enable cooperative transmission, sensors are divided into groups where sensors in each group help each other in transmitting their decisions in a way that the fusion center receives each local decision as an orthogonal frequency division multiplexed (OFDM) block. The fusion center detects all OFDM blocks sent by all groups to process them in order to obtain a final (global) decision. Using this cooperative transmission scheme enables the fusion center to apply diversity combining methods in order to reduce the fading effects of the channel. Optimal and sub-optimal fusion rules are derived for such system. Simulation results are provided to show the performance improvement that can be obtained compared to the conventional system where each local decision is transmitted to the fusion center individually and no diversity technique is applied at the fusion center.  相似文献   
54.
The role of beta3- and other putative atypical beta-adrenoceptors in human white adipocytes and right atrial appendage has been investigated using CGP 12177 and novel phenylethanolamine and aryloxypropanolamine beta3-adrenoceptor (beta3AR) agonists with varying intrinsic activities and selectivities for human cloned betaAR subtypes. The ability to demonstrate beta1/2AR antagonist-insensitive (beta3 or other atypical betaAR-mediated) responses to CGP 12177 was critically dependent on the albumin batch used to prepare and incubate the adipocytes. Four aryloxypropanolamine selective beta3AR agonists (SB-226552, SB-229432, SB-236923, SB-246982) consistently elicited beta1/2AR antagonist-insensitive lipolysis. However, a phenylethanolamine (SB-220646) that was a selective full beta3AR agonist elicited full lipolytic and inotropic responses that were sensitive to beta1/2AR antagonism, despite it having very low efficacies at cloned beta1- and beta2ARs. A component of the response to another phenylethanolamine selective beta3AR agonist (SB-215691) was insensitive to beta1/2AR antagonism in some experiments. Because no [corrected] novel aryloxypropanolamine had a beta1/2AR antagonist-insensitive inotropic effect, these results establish more firmly that beta3ARs mediate lipolysis in human white adipocytes, and suggest that putative 'beta4ARs' mediate inotropic responses to CGP 12177. The results also illustrate the difficulty of predicting from studies on cloned betaARs which betaARs will mediate responses to agonists in tissues that have a high number of beta1- and beta2ARs or a low number of beta3ARs.  相似文献   
55.
Since little has been known about the properties of aromatic analogues of the antineoplastic agent methylglyoxal bis(guanylhydrazone) (MGBG), an investigation was performed on phenylglyoxal bis(guanylhydrazone) (PhGBG). PhGBG competitively inhibited yeast adenosylmethionine decarboxylase (AdoMetDC) with a Ki of 65 microM. As compared to MGBG (Ki 0.23 microM), PhGBG is a much weaker inhibitor, being even weaker than the unsubstituted congener glyoxal bis(guanylhydrazone) (GBG, Ki 18 microM). PhGBG inhibited porcine kidney diamine oxidase (DAO) non-competitively, being a more potent inhibitor (Ki 0.12 microM) than GBG (Ki 0.17 microM) or MGBG (Ki 0.33 microM). Thus, PhGBG has an unfavourably high ratio of Ki(AdoMetDC)/Ki(DAO) for potential use for selectively inhibiting polyamine biosynthesis. This does not exclude the possibility that PhGBG or other aromatic congeners might have therapeutic value since the corresponding ratio of the antileukaemic congeners GBG and MGBG is also high as compared to many aliphatic non-antileukaemic analogues. The pKa1 and pKa2 values of PhGBG dication were found to be 6.39 +/- 0.02 and 8.64 +/- 0.02 respectively, their difference being distinctly larger than in the case of GBG or its C-alkylated analogues. This may result from decreased stability of the dication form, caused by the resonance effect or possibly by the inductive effect of the phenyl group. The species distribution of PhGBG (proportion of free base 5.5%, predominant species the monocation) at 37 degrees C resembles that of GBG and MGBG but is clearly different from that of non-antileukaemic C-alkylated analogues. These similarities suggest that PhGBG and its derivatives may be worth antitumour screening. Depending on the conditions used in the crystallization, three different types of crystals of PhGBG sulphate were obtained. Crystallography indicated that, in two of the types, the crystal consisted exclusively of the anti-anti isomer, i.e. the same isomer as has been observed in the case of GBG and its C-alkylated congeners. One crystal type, however, consisted of a different geometrical isomer (anti-syn), suggesting that PhGBG may isomerize more easily than its aliphatic analogues. Previous concepts on the isomerism of GBG and C-alkylated bis(guanylhydrazones) thus cannot be generalized to aromatic congeners. A theory based on resonance, inductive and hyperconjugative effects and electron transfers is presented that is capable of explaining the formation of the two geometrical isomers of PhGBG that were experimentally observed. A similar theory, based on hyperconjugation of C-F bonds, is presented that is capable of explaining the previous finding of the formation of the anti-syn isomer of trifluoromethylglyoxal bis(guanylhydrazone) (CF3GBG). Like that of CF3GBG, the anti-syn isomer of the PhGBG dication is stabilized by an internal hydrogen bond. The lack of structural rigidity may affect the biological properties of PhGBG, e.g. its ability to inhibit AdoMetDC.  相似文献   
56.
先进电子系统的功能与特性的整合在持续快速发展,这导致了目前时钟网络设计中的许多主要障碍。为满足各种芯片和接口在频率、I/O和性能方面对时钟的需求,经常需要既没有灵活性,也不具备便携性的非常精确的执行。最终的结果往往是一个由多个分散的振荡器和缓冲器组成的支离破碎的解决方案,只要系统要求不改变,它就可以工作。这种方法会使物料成本(BOM)、库存管理和设计资源的成本居高不下。进入新的多PLL时代,可编程时钟通过采用I2C和JTAG这样的行业标准接口,加上非易失性存储器就可以达到解决这些挑战的目标。通过通用接口实现系统内…  相似文献   
57.
STUDY OBJECTIVE: To estimate the extent to which changes in blood pressure, smoking, and serum cholesterol concentration explain the observed increase in socioeconomic differences in mortality from ischaemic heart disease (IHD) in Finland during the past 20 years. DESIGN: Predicted changes in mortality from IHD were calculated using logistic regression models with the risk factor levels assessed by cross sectional population surveys conducted in 1972, 1977, 1982, and 1987. The subjects included white collar and blue collar workers and farmers. The predicted changes were compared with the observed mortality changes in the same socioeconomic groups in the total population of the same geographical area. SETTING: North Karelia and Kuopio provinces, eastern Finland. PARTICIPANTS: 16,741 men and 16,389 women aged 30-59 randomly drawn from the population registers of the study areas. Mortality data were obtained from the total population in the same areas. MAIN RESULTS: In men, the changes in diastolic blood pressure, total serum cholesterol, and smoking predicted a 28% decline in the mortality from IHD among white collar workers, a 30% decline among blue collar workers, and a 33% decline in farmers. Observed declines in the same socioeconomic groups were 61%, 40%, and 37%, respectively. In women, the predicted decline was 41% among white collar workers, 35% among blue collar workers, and 39% among farmers. The respective observed declines were 57%, 43%, and 20%. CONCLUSIONS: Less than half of the decline in IHD mortality among white collar men was explained by the risk factor changes, while they explained 75% of the decline among blue collar men and 89% of the decline among male farmers. Changes in risk factors did not explain the increasing difference in IHD mortality between the socioeconomic groups, especially among men.  相似文献   
58.
Dielectric constant (DEC) of internal phase influenced the zeta potential (ZP) of o/w emulsion prepared with or without emulgent. In both systems ZP and DEC of internal phase exhibited an approximately linear relationship. Using homologous aliphatic hydrocarbons as internal phases, emulsions were prepared with polysorbate-80. Increase in carbon chain length brought about increase in interracial area and decrease in ZPs of emulsions. A fair inverse correlation between ZP and DEC of internal phase was revealed in this series. Increase in phase volume ratio from 0.05 to 0.3 brought about limited changes in ZPs whereas by further increasing phase volume ratio, ZP decreased steadily. Studies pertaining to the effect of phase volume ratio on DEC of o/w emulsions are in accordance with earlier observations. Increase in phase volume ratio causes a steady decrease in DEC of emulsion. Of the five equations employed, the Bruggeman equation appears to predict the observed values more accurately.  相似文献   
59.
This communication gives an outline of a user-friendly PC wde developed for preliminary design of a fluid bed dryer (FBD) and its essential ancillaies e.g. cyclone, fan etc.. The fluid bed dryer may have internal heat exchangers. Correlations used for design calculations are presented. The program permits estimation of the energy consumption as well as the installed and operating costs.  相似文献   
60.
This paper deals with studies on the dilute solution properties of methyl methacrylate—acrylonitrile copolymer of 0.289 mole fraction (mf) of acrylonitrile composition. Mark—Houwink parameters for this copolymer have been evaluated in acetonitrile (MeCN), 2-butanone (MEK), dimethylformamide (DMF) and γ-butyrolactone (γ-BL). The solvent power is found to be in the order of MEK < MeCN < DMF < γ-BL at 30°C. Herein, probably for the first time, the steric factor for the copolymer is found to be lower than that for the parent homopolymers and the excess interaction parameter, χAB is found to be negative. This probably suggests that the units are compatible to each other.  相似文献   
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