全文获取类型
收费全文 | 3324篇 |
免费 | 270篇 |
国内免费 | 13篇 |
专业分类
电工技术 | 21篇 |
综合类 | 4篇 |
化学工业 | 822篇 |
金属工艺 | 135篇 |
机械仪表 | 227篇 |
建筑科学 | 53篇 |
能源动力 | 123篇 |
轻工业 | 377篇 |
水利工程 | 27篇 |
石油天然气 | 2篇 |
无线电 | 564篇 |
一般工业技术 | 674篇 |
冶金工业 | 176篇 |
原子能技术 | 38篇 |
自动化技术 | 364篇 |
出版年
2024年 | 3篇 |
2023年 | 57篇 |
2022年 | 72篇 |
2021年 | 118篇 |
2020年 | 95篇 |
2019年 | 107篇 |
2018年 | 110篇 |
2017年 | 131篇 |
2016年 | 175篇 |
2015年 | 116篇 |
2014年 | 193篇 |
2013年 | 244篇 |
2012年 | 251篇 |
2011年 | 301篇 |
2010年 | 223篇 |
2009年 | 179篇 |
2008年 | 192篇 |
2007年 | 154篇 |
2006年 | 125篇 |
2005年 | 106篇 |
2004年 | 74篇 |
2003年 | 74篇 |
2002年 | 79篇 |
2001年 | 76篇 |
2000年 | 47篇 |
1999年 | 50篇 |
1998年 | 83篇 |
1997年 | 35篇 |
1996年 | 32篇 |
1995年 | 18篇 |
1994年 | 12篇 |
1993年 | 10篇 |
1992年 | 4篇 |
1991年 | 9篇 |
1990年 | 11篇 |
1989年 | 9篇 |
1988年 | 7篇 |
1987年 | 6篇 |
1986年 | 4篇 |
1985年 | 4篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1975年 | 2篇 |
1966年 | 1篇 |
排序方式: 共有3607条查询结果,搜索用时 15 毫秒
181.
Koji Fushimi Takatoshi Shimada Hiroki Habazaki Hidetaka Konno Masahiro Seo 《Electrochimica acta》2011,(4):1773
Depassivation–repassivation of iron surfaces in boric–borate solutions were investigated by using the micro-indentation test. A pair of current peaks due to repair of the passive film following rupture of the film were observed during a series of indenter drives, i.e., loading and unloading of the indenter. The shape of the current peak depended on environmental conditions (conductivity and pH of the solution) and substrate conditions (mechanical processing history, alloyed element) as well as indentation conditions (repetition, maximum depth, and maximum load). Plastic deformation of the surface was accompanied by surface depassivation, while no depassivation occurred during the elastic deformation, indicating that the passive film on iron has a ductile property. The solution conditions did not affect the scale of depassivation but affected the rate of repassivation. Dislocations in the substrate made surface depassivation difficult but enhanced reactivity during the repassivation. The test also revealed that type-312L stainless steel has high corrosion resistance in a concentrated NaCl solution. 相似文献
182.
Jung II-Ho Hwi Seo Jong Choi Sung-Jin Tae-Won Park Jang-Bom Chai 《Journal of Mechanical Science and Technology》2005,19(1):336-342
The DC motor of a vehicle may cause noise and vibration due to high-speed revolution, which can make a driver feel uncomfortable There have been various studies attempting to solve these problems, mostly focusing on the causes of noise and vibration and a means of preventing them The CAE methodology is more efficient than a real test for the purpose of looking for various design parameters to reduce the noise and vibration of the DC motor In this study, a design process for reducing brush noise is presented with the use of a computer model, which is made by using a multi-body dynamics program (DADS) The design parameters to reduce the brush noise and vibration were proposed using a computer model They were used to reduce the noise and vibration of the DC motor and verified by the test tesults of the fan DC motor in the vehicle This method may be applicable to various DC motors 相似文献
183.
Hong-Jae Lee Dong-Min Lee Min-Ji Seo Ho-Chul Kang Seok-Kyu Kwon Kyeong-Sook Choi 《International journal of molecular sciences》2022,23(5)
PSMD14, a subunit of the 19S regulatory particles of the 26S proteasome, was recently identified as a potential prognostic marker and therapeutic target in diverse human cancers. Here, we show that the silencing and pharmacological blockade of PSMD14 in MDA-MB 435S breast cancer cells induce paraptosis, a non-apoptotic cell death mode characterized by extensive vacuolation derived from the endoplasmic reticulum (ER) and mitochondria. The PSMD14 inhibitor, capzimin (CZM), inhibits proteasome activity but differs from the 20S proteasome subunit-inhibiting bortezomib (Bz) in that it does not induce aggresome formation or Nrf1 upregulation, which underlie Bz resistance in cancer cells. In addition to proteasome inhibition, the release of Ca2+ from the ER into the cytosol critically contributes to CZM-induced paraptosis. Induction of paraptosis by targeting PSMD14 may provide an attractive therapeutic strategy against cancer cells resistant to proteasome inhibitors or pro-apoptotic drugs. 相似文献
184.
Yeon-Mi Hong Seo Yeon Min Dayeong Kim Subin Kim Daekwan Seo Kyoung Hwa Lee Sang Hoon Han 《International journal of molecular sciences》2022,23(5)
Attenuating the expression of immediate early (IE) proteins is essential for controlling the lytic replication of human cytomegalovirus (HCMV). The human microRNAs (hsa-miRs), miR-200b-3p and miR-200c-3p, have been identified to bind the 3′-untranslated region (3′-UTR) of the mRNA encoding IE proteins. However, whether hsa-miRs can reduce IE72 expression and HCMV viral load or exhibit a crosstalk with the host cellular signaling machinery, most importantly the NF-κB cascade, has not been evaluated. In this study, argonaute-crosslinking and immunoprecipitation-seq revealed that miR-200b-3p and miR-200c-3p bind the 3′-UTR of UL123, which is a gene that encodes IE72. The binding of these miRNAs to the 3′-UTR of UL123 was verified in transfected cells stably expressing GFP. We used miR-200b-3p/miR-200c-3p mimics to counteract the downregulation of these miRNA after acute HCMV infection. This resulted in reduced IE72/IE86 expression and HCMV VL during lytic infection. We determined that IE72/IE86 alone can inhibit the phosphorylation of RelA/p65 at the Ser536 residue and that p-Ser536 RelA/p65 binds to the major IE promoter/enhancer (MIEP). The upregulation of miR-200b-3p and miR-200c-3p resulted in the phosphorylation of RelA/p65 at Ser536 through the downregulation of IE, and the binding of the resultant p-Ser536 RelA/p65 to MIEP resulted in a decreased production of pro-inflammatory cytokines. Overall, miR-200b-3p and miR-200c-3p—together with p-Ser536 RelA/p65—can prevent lytic HCMV replication during acute and latent infection 相似文献
185.
Byoung Ok Cho Chang Wook Lee Yangkang So Chang Hyun Jin Si Yong Kang Dong Sub Kim Kwon Il Seo Hong Sun Yook Il Yun Jeong 《Food science and biotechnology》2014,23(4):1313-1319
The protective effect of cyanidin-3-glucoside (C3G) against carbon tetrachloride (CCl4)-induced liver injury in mice was investigated. Administration of C3G attenuated the levels of serum aspartate aminotransferase, alanine aminotransferase, and liver lipid peroxidation in CCl4-treated mice. Histopathological examination of mouse livers showed that C3G reduced the incidence of liver lesions induced by CCl4. Moreover, C3G prevented DNA damage and decreased the protein levels of γ-H2AX in CCl4-treated mouse livers. C3G also increased the activity of the antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase, which were decreased due to CCl4 administration in CCl4-treated mouse livers. C3G inhibited the expression levels of IL-6 and iNOS in CCl4-treated mice. C3G apparently protects the liver from CCl4-induced hepatic damage through antioxidant and anti-inflammatory mechanisms. 相似文献
186.
Qi-Ming Yu Eun-Ji Lim Soo-Kyong Choi Jung-Sook Seo 《Food science and biotechnology》2014,23(3):849-857
This study was conducted to investigate the effect of grapevine leaf extract (GLE) on the oxidative stress of rats fed a high-fat diet. Rats were divided into six groups: a normal diet with 0% (NC), 1.0% (NG1.0), and 1.5% GLE (NG1.5); and a high-fat diet with 0% (HFC), 1.0% (HFG1.0), and 1.5% GLE (HFG1.5). Treatment with GLE to the high-fat diet reduced lipid peroxide concentrations in plasma and liver compared to those of HFC rats. Total glutathione and GSH/GSSG of the groups with GLE were higher than those of untreated groups. Hepatic glutathione peroxidase, glutathione-S-transferase, and glutathione reductase activities along with catalase and glutathione peroxidase activities in erythrocytes increased after GLE treatment to high-fat diet compared with HFC rats. Hepatic retinol and tocopherol increased in HFG1.5 group compared to those of HFC group. These results indicate that GLE can protect against oxidative stress induced by a high-fat diet in rats. 相似文献
187.
Jung Sang Cho Jeong-Cheol Lee Shin Hye Chung Jeong Kon Seo Sang-Hoon Rhee 《Ceramics International》2014
The effect of grain size and density of hydroxyapatite particles, which were prepared by different spray-pyrolysis temperatures, on the sinterability of hydroxyapatite disk was investigated. Calcium phosphate solution (Ca/P ratio of 1.67 and 0.1 M concentration) was prepared by reacting calcium nitrate tetrahydrate and diammonium hydrogen phosphate solutions, and adding nitric acid. Spray-pyrolysis was carried out at 900 °C, 1200 °C, and 1500 °C at a carrier gas flowing rate of 10 L/min. The particles synthesized at 900 °C were large, hollow spheres with a hole at the outer surface, a broad size distribution, but had small grain sizes. Conversely, the particles synthesized at 1500 °C were small, solid spheres with a narrow size distribution, but had large grain sizes. The particles synthesized at 1200 °C had intermediate properties. A sinterability test conducted at 1100 °C for 1 h demonstrated that small and dense particles with large grain sizes showed a higher relative sintered density compared with large and hollow particles with small grain sizes. The results were explained in terms of the grain size and density of a particle, which were inversely and proportionally affected to sinterability. The practical implication of these results is that highly sinterable hydroxyapatite powders can be synthesized through spray-pyrolysis at a high temperature under a fixed initial concentration of calcium phosphate solution and flow rate of carrier gas. 相似文献
188.
Utilisation possibility of Enterococcus faecalis isolates from neonate's faeces for production of fermented sausages as starter cultures
下载免费PDF全文
![点击此处可从《International Journal of Food Science & Technology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Hoa Van Ba Hyun‐Woo Seo Soo‐Hyun Cho Yoon‐Seok Kim Jin‐Hyoung Kim Beom‐Young Park Hyun‐Wook Kim Jun‐Sang Ham Pil‐Nam Seong 《International Journal of Food Science & Technology》2017,52(7):1660-1669
This study aimed at assessing the utilisation possibility of Enterococcus faecalis as starter cultures for production of fermented sausages. The E. faecalis isolates isolated from faeces samples of 5‐day‐old healthy newborn babies, identified by 16SrDNA sequencing and free from virulence determinants as proven by genomic sequencing, were used for fermented sausages production as starter culture. Six treatments (four inoculated with four different E. faecalis isolates, one with commercial starter culture and one control) were prepared. The inoculation with E. faecalis showed a stronger acidification compared with the control. The treatments with E. faecalis showed significantly higher flavour and acceptability scores in comparison with the control or commercial starter culture. Both of commercial starter culture and E. faecalis were positive with tyramine. Apart from the amine production, the inoculation with E. faecalis generally improved the acidifying activity and flavour of the products, suggesting their application potentials in fermented sausages production as starter cultures. 相似文献
189.
Jungmin Kim Minhhuy Le Juhyeon Park Heejoon Seo Gyejo Jung Jinyi Lee 《Journal of Mechanical Science and Technology》2018,32(2):623-630
Tubular-type transmission towers have several advantages, but could be compromised if welding defects from the construction process are not found during deployment. This research derived an equation that illustrates how a change in stress accompanied with mechanical deformation triggered a change in distribution of magnetic flux density. Furthermore, it verified experimentally that a change in distribution of magnetic flux density occurred due to a change in stress at the welding zone. Using this principle, this research proposes a system to measure residual stress occurred in the welding zone of tubular-type transmission tower. The ultrasound examination results were compared and the result showed that ultrasound signals revealed defects in a place where sudden distribution of magnetic flux density was presented. However, when a number of welding defects occurred across the large area, the distribution of magnetic flux density may not change due to the alleviating effect of the stress concentration. 相似文献
190.
Kum Hee Lee Hyun Ju Kang Seok Jae Lee Ji Hyun Seo Young Kwan Kim Seung Soo Yoon 《Synthetic Metals》2011,161(11-12):1113-1121
A series of new iridium complexes with 5-acetyl-2-phenylpyridine derivatives as ligands was developed. The complexes exhibited high EL performance when applied to OLEDs. These materials showed red emission with a peak at 575–636 nm. In particular, one of the devices in this study showed a maximum luminous efficiency, maximum power efficiency, external quantum efficiency and CIE coordinates of 29.0 cd/A, 6.13 lm/W, 8.86% at 20 mA/cm2 and (0.57, 0.43) at 10 V, respectively. In addition, a deep red OLED with CIE coordinates of (0.67, 0.32) at 10 V exhibited a maximum luminous efficiency, maximum power efficiency and external quantum efficiency of 5.61 cd/A, 1.02 lm/W and 5.35% at 20 mA/cm2, respectively. 相似文献