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排序方式: 共有492条查询结果,搜索用时 15 毫秒
91.
92.
功能纤维的现状和展望 总被引:3,自引:0,他引:3
综述了日本已开发的功能纤维的品种 ,技术措施 ;日本、美国在新世纪研究开发新纤维的规划、设想 ,中长期开发课题、技术战略 ,指出了 2 1世纪功能纤维的开发应用前景。 相似文献
93.
Brett J West Hisanori Tani Afa K Palu Charles B Tolson C Jarakae Jensen 《Journal of the science of food and agriculture》2007,87(14):2583-2588
BACKGROUND: Noni (Morinda citrifolia L.) leaves have a documented history of food use. However, previous safety and antinutrient studies are absent. The current investigation was conducted to assess the utility of noni leaves as food. RESULTS: No evidence of toxicity or differences in weight gain were observed in acute, subacute, and subchronic oral toxicity tests of ethanol–water (1:1 v/v) and hot‐water extracts of noni leaves in mice at doses of 2000, 200, and 20 mg kg?1 body weight, respectively. Acute systemic anaphylaxis tests of the ethanol–water (4:1 v/v) and hot‐water extracts were negative. Further, leaf proteins were readily digested in simulated gastric fluid. Tannic acid concentrations in frozen and dried leaf were 1.6 and 25.8 g kg?1, respectively. Phytic acid was not detected in the raw leaf (<1 g kg?1). The average oxalic acid content was 1 g kg?1 and was fairly uniform among 22 leaf samples from 11 islands throughout French Polynesia. Similarly, campesterol, stigmasterol, and β‐sitosterol content did not vary widely, suggesting low inter‐island content variability. CONCLUSIONS: The apparent lack of toxicity of the leaves and the hardiness of the plant make it ideal for further agricultural development, especially where sustained growth of other food crops is difficult. Copyright © 2007 Society of Chemical Industry 相似文献
94.
Jia Shi Riku Kanoya Yurina Tani Sodai Ishikawa Rino Maeda Sana Suzuki Fumiya Kawanami Naoko Miyagawa Katsuhiko Takahashi Teruaki Oku Ami Yamamoto Kaori Fukuzawa Motowo Nakajima Tatsuro Irimura Nobuaki Higashi 《International journal of molecular sciences》2022,23(9)
We examined whether sulfated hyaluronan exerts inhibitory effects on enzymatic and biological actions of heparanase, a sole endo-beta-glucuronidase implicated in cancer malignancy and inflammation. Degradation of heparan sulfate by human and mouse heparanase was inhibited by sulfated hyaluronan. In particular, high-sulfated hyaluronan modified with approximately 2.5 sulfate groups per disaccharide unit effectively inhibited the enzymatic activity at a lower concentration than heparin. Human and mouse heparanase bound to immobilized sulfated hyaluronan. Invasion of heparanase-positive colon-26 cells and 4T1 cells under 3D culture conditions was significantly suppressed in the presence of high-sulfated hyaluronan. Heparanase-induced release of CCL2 from colon-26 cells was suppressed in the presence of sulfated hyaluronan via blocking of cell surface binding and subsequent intracellular NF-κB-dependent signaling. The inhibitory effect of sulfated hyaluronan is likely due to competitive binding to the heparanase molecule, which antagonizes the heparanase-substrate interaction. Fragment molecular orbital calculation revealed a strong binding of sulfated hyaluronan tetrasaccharide to the heparanase molecule based on electrostatic interactions, particularly characterized by interactions of (−1)- and (−2)-positioned sulfated sugar residues with basic amino acid residues composing the heparin-binding domain-1 of heparanase. These results propose a relevance for sulfated hyaluronan in the blocking of heparanase-mediated enzymatic and cellular actions. 相似文献
95.
Asahiro Morishita Kyoko Oura Tomoko Tadokoro Koji Fujita Joji Tani Tsutomu Masaki 《International journal of molecular sciences》2021,22(7)
The liver is well recognized as a non-immunological visceral organ that is involved in various metabolic activities, nutrient storage, and detoxification. Recently, many studies have demonstrated that resident immune cells in the liver drive various immunological reactions by means of several molecular modulators. Understanding the mechanistic details of interactions between hepatic host immune cells, including Kupffer cells and lymphocytes, and various hepatic pathogens, especially viruses, bacteria, and parasites, is necessary. MicroRNAs (miRNAs), over 2600 of which have been discovered, are small, endogenous, interfering, noncoding RNAs that are predicted to regulate more than 15,000 genes by degrading specific messenger RNAs. Several recent studies have demonstrated that some miRNAs are associated with the immune response to pathogens in the liver. However, the details of the underlying mechanisms of miRNA interference in hepatic host–pathogen interactions still remain elusive. In this review, we summarize the relationship between the immunological interactions of various pathogens and hepatic resident immune cells, as well as the role of miRNAs in the maintenance of liver immunity against pathogens. 相似文献
96.
Tani Hiroshi Lu Renguo Koganezawa Shinji Tagawa Norio 《Microsystem Technologies》2021,27(6):2243-2255
Microsystem Technologies - The formation of head smears during the heat-assisted magnetic recording is a significant problem that must be addressed to ensure the reliability of the head-disk... 相似文献
97.
For the optimum design of photovoltaic power systems, it is very important to estimate their annual maximum amount of output. In general, the annual maximum amount of output has been calculated by using photovoltaic module efficiency under irradiance of 1 kW/m2 at AM 1.5 with solar cell temperature of 25°C. Since the spectral distribution of solar radiation changes with weather, season and time, the efficiency of solar cells is not always constant. This paper describes a method evaluating the maximum amount of output in photovoltaic modules, ‘the spectral method,’ by using the measured annual spectral solar radiation and the spectral response of various photovoltaic modules. The calculated values using the spectral method agreed well with the measured values for amorphous silicon photovoltaic modules from March 1991 to February 1992. The spectral method proved most effective for optimum design of amorphous silicon photovoltaic power systems. 相似文献
98.
Eight calves cloned from somatic cells of a single adult 总被引:3,自引:0,他引:3
Y Kato T Tani Y Sotomaru K Kurokawa J Kato H Doguchi H Yasue Y Tsunoda 《Canadian Metallurgical Quarterly》1998,282(5396):2095-2098
Eight calves were derived from differentiated cells of a single adult cow, five from cumulus cells and three from oviductal cells out of 10 embryos transferred to surrogate cows (80 percent success). All calves were visibly normal, but four died at or soon after birth from environmental causes, and postmortem analysis revealed no abnormality. These results show that bovine cumulus and oviductal epithelial cells of the adult have the genetic content to direct the development of newborn calves. 相似文献
99.
Kawano T. Kato Y. Tani R. Takao H. Sawada K. Ishida M. 《Electron Devices, IEEE Transactions on》2004,51(3):415-420
This paper reports on a fabrication technique for realizing micro-Si probe arrays with MOSFETs on the same Si substrate. Micro-Si probe arrays have been successfully fabricated on Si (111) substrates by selective vapor-liquid-solid (VLS) growth using catalytic Au dot arrays and Si/sub 2/H/sub 6/ used as the gas source for a molecular-beam-epitaxy. The Si probes can be grown at temperatures ranging from 500/spl deg/C to 700/spl deg/C. In this paper, MOSFETs were fabricated on Si (111) substrates and Au dots were placed at the drain regions of the MOSFETs in order to grow the Si probes. VLS growth at 700/spl deg/C for 2 h was carried out on these substrates. Consequently, the MOSFETs can be used in on-chip circuits for the VLS-Si probe array. The electrical characteristics of the MOSFETs were measured before and after the VLS process. After the VLS process, no changes in the MOSFET characteristics were observed due to the effects of Au-diffusion, and the results confirmed that VLS growth at a temperature of 700/spl deg/C allows fabrication of micro-Si probes without deterioration of the MOSFETs. VLS-Si probes with controlled conductance were realized. The as-grown Si probes were of high resistance, but could be changed to various conductivities by impurity diffusion. 相似文献
100.