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41.
梁岳  单娜琳 《石油仪器》2012,26(6):55-57,104
文章给出了一种依托于计算机开发的储层预测方法。针对D气田石盒子组盒2+3段储层预测的技术难点,在分析储层地球物理参数特征的基础上,摸索一套具有较高精度的储层预测应用技术方法。论述了逐级控制下的一体化储层预测技术,给出了这种方法的思路、原理、实现过程及应用实例,分析了方法的应用精度。对复杂区储层预测具有一定的参考价值。  相似文献   
42.
Effective extraction of algal bioactive compounds can be achieved by treatments such as pH control, heat and enzymatic hydrolysis. Hizikia fusiformis antioxidants were extracted with those treatments individually and extraction efficacies were compared by measuring yield, total phenolic content and antioxidant activities. Increased pH could successfully improve the extraction, and incubation at pH 12.0 for 12 h was the most effective pH treatment. Incubation at 100 °C for 45 min was significantly (P < 0.05) more effective than the other heat treatments. Optimum condition for enzymatic treatment was combination of 2% Alcalase (alkaline endopeptidase/protease) and 3% Ultraflo (β‐glucanase/carbohydrase) at pH 8.0 and 54–58 °C for 24 h. Integration of those optimised treatments in the extraction sequence of heat (H), enzymatic hydrolysis (E) and pH control (P) was the most effective sequence. Compared with other extraction sequences, HEP sequence indicated significantly higher phenolic content and antioxidative activities in 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and hydrogen peroxide scavenging assays.  相似文献   
43.
CdSe films about 1 μm thick were vacuum deposited on unheated glass substrates. Reflection electron diffraction studies showed the growth of a one-dimensional {00.1} texture orientation of the hexagonal phase. Films of lower resistivity were characterized by a larger grain size and better ordering, whilst films of higher resistivity contained amorphous regions and were less ordered. A study of the carrier type, the concentration, the Hall mobility and the variation in the bond length u along the hexagonal c axis of “as-deposited” and heat-treated films showed that the lower resistivity films incorporated a small cadmium excess, which increased with heat treatment, resulting in higher carrier concentrations and a further lowering of the resistivity. Large increases in the resistivities of films deposited at high rates were attributed to the depletion of the small individual grains.  相似文献   
44.
Abstract

Suitability of oxide electronic conductors [e.g. ruthenium oxide (RuOx) and indium-tin-oxide (ITO)] as contact metallization for ferroelectric films (e.g. PbZrxTi1?xO3) was investigated using techniques such as Rutherford backscattering spectrometry, x-ray diffraction and electron spectroscopy for chemical analysis. Thin films of RuOx and ITO were deposited on Si substrates by reactive sputtering. Either PbO or PZT (x = 0.53) films were deposited onto the conducting oxides and the specimens were annealed at various temperatures between 400°C and 700°C. Less intermixing was found in Si/RuOx/ PZT films when compared to Si/ITO/PZT under similar processing conditions. The ferroelectric properties of PZT films on RuOx electrodes are compared to those on Pt electrodes. The PZT films show improved fatigue properties on RuOx electrodes.  相似文献   
45.
Fecal bile acid and neutral sterol patterns were studied in eight healthy adult volunteers who were challenged withVibrio cholerae classical Ogawa 395 strain in the course of vaccine development studies. Bacterial 7α-dehydroxylation of cholic and chenodeoxycholic acids was not altered during experimentally induced cholera diarrhea, despite the fact that fecal weight in g/day (wet wt) was increased greatly during diarrhea (1913±390 vs 161±11 in controls, p<0.005). Consistent with the findings on bile acids, no significant changes in the production of coprostanol, epicoprostanol, or coprostanone were observed although the percentage of unmodified cholesterol was increased during the diarrheal episode (20.7±3.3% vs 11.9±2.3, p<0.02). Total concentrations of both bile acids and cholesterol in mg/g of feces (wet wt) were decreased considerably as a result of diarrhea). However, total bile acid and neutral steroid excretions in mg/kg/day in subjects with and without diarrhea do not appear to be different. Intestinal transit times, measured in eight subjects by the use of carmine red dye, were found to be shortened in diarrhea (5.8±1.1 hr vs 23.4±4.1 hr in controls, p<0.001). The results from this study are similar to those observed in experimentally induced travellers' diarrhea associated with toxigenicEscherichia coli, but they are in striking contrast to the changes in gastrointestinal steroid metabolism observed in acute shigello sis, an invasive intestinal infection.  相似文献   
46.
起伏界面折射波时距曲线及其解释   总被引:1,自引:0,他引:1  
推导出向、背型地质界面上的折射波时距曲线方程。此曲线形态与水平、倾斜、直立界面上的时距曲线相似。因此,折射波时距曲线反演具有多解性,利用追逐和相遇时距曲线观测系统获得实测数据,结合广义互换时法中的速度分析判断界面形态,可以减小或消除多解性。对比了t0法与广义互换时的优缺点,并举例说明广义互换时法可更详细地确定界面形态。  相似文献   
47.
复杂起伏地表尤其山地表层结构下的速度分析的精度直接受到浮动基准面的选择的影响,本文推导出在浮动基准面上速度分析误差公式,指出基于浮动基准面上的速度分析的误差与替换层的速度成正比,与浮动基准面与水平观测面的高程差成正比,与目的层埋深成反比。同时,基于理论模型,定量分析了浮动基准面上速度分析的误差,为速度误差校正提供了依据;也验证了基于浮动基准面上的速度分析的误差比基于固定基准面上的速度分析误差小。  相似文献   
48.
A solution growth approach for zinc oxide (ZnO) nanowires is highly appealing because of the low growth temperature and possibility for large area synthesis. Reported reaction times for ZnO nanowire synthesis, however, are long, spanning from several hours to days. In this work, we report on the rapid synthesis of ZnO nanowires on various substrates (such as poly(ethylene terephthalate) (PET), silicon and glass) using a commercially available microwave oven. The average growth rate of our nanowires is determined to be as high as 100?nm?min(-1), depending on the microwave power. Transmission electron microscopy analysis revealed a defect-free single-crystalline lattice of the nanowires. A detailed analysis of the growth characteristics of ZnO nanowires as functions of growth time and microwave power is reported. Our work demonstrates the possibility of a fast synthesis route using microwave heating for nanomaterials synthesis.  相似文献   
49.
The dramatic rise in mobile applications has greatly increased threats to the security and privacy of users. Security mechanisms on mobile devices are currently limited, so users need more expressive ways to ensure that downloaded mobile applications do not act maliciously. Policy-specification languages were created for this purpose; they allow the enforcement of user-defined policies on third-party applications. We have implemented LoPSiL, a location-based policy-specification language for mobile devices. This article describes LoPSiL’s design and implementation, several example policies, and experiments that demonstrate LoPSiL’s viability for enforcing policies on mobile devices.  相似文献   
50.
Fecal steroid compositions of 82 human subjects of various ages and diets and gastrointestinal status were examined by gas liquid chromatography. Progressive increases in bacterial activities on both bile acids and neutral sterols were observed with the advance of age in infants and children. The patterns in the 4-year-olds approached those observed in adults. Bacterial activites on fecal steroids were found to be decreased in adult subjects with acute shigellosis and in those challenged by castor oil. In contrast, no significant changes in fecal steroid profiles were observed in the subjects with traveller's diarrhea assoicated with toxigenicEscherichia coli. The effects of diarrhea on fecal steroids of infants under 11/2 years were less consistent than those of adults. However, a close relationship was observed between the degree of 7α-dehydroxylation of cholic acid (expressed as the ratio of deoxycholic to the sum of deoxycholic and cholic acids) and the percentage of cholesterol in the feces (r= 0.921, p<0.001). The correlation between the production of lithocholic acid and the percentage cholesterol was also good (r=−0.739, p<0.001). Analysis of neutral steroids may be a good index of intraluminal bile acid metabolism.  相似文献   
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