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91.
Cysteine protease activity in mycelial culture increased 7.7-fold after fruit body formation in Pleurotus ostreatus, using the Leu pNA (LPNA) cleavage assay. The enzyme was purified from fruit bodies and its M(r) was 97,000 by gel filtration and 48,500 by SDS-PAGE, indicating that it is a dimer. The enzyme was sensitive to iodoacetic acid, p-chloromercuribenzoate, N-ethylmaleimide, and HgCl2. The sequence of the first 9 N-terminal amino acids of cysteine protease was ASGLXXAIL. 相似文献
92.
VJ Paul Y Seo KW Cho JR Rho J Shin PR Bergquist 《Canadian Metallurgical Quarterly》1997,60(11):1115-1120
Ten sesquiterpenoids, including seven new ones, have been isolated from an undescribed sponge of the genus Dysidea. Compounds 1-8 are sesquiterpenoids of the drimane class, while 9 and 10 are 12-norsesquiterpenoids of the same structural class. The structures of novel compounds have been determined by combined spectroscopic methods. These compounds exhibited moderate antimicrobial and enzyme inhibitory (Na+/K(+)-ATPase and PLA2) activities. 相似文献
93.
Ali Hussein F. M. Khan Abdul Manan Baek Hangyeol Shin Buhyun Kim Youngshik 《Microsystem Technologies》2021,27(6):2481-2492
Microsystem Technologies - In this research a biologically inspired finger-like mechanism similar to human musculoskeletal system is developed based on Shape Memory Alloys (SMAs). SMA actuators are... 相似文献
94.
Feng Zhong Chai Kiat Yeo Bu Sung Lee 《Journal of Network and Computer Applications》2012,35(1):316-327
In places where mobile users can access multiple wireless networks simultaneously, a multipath scheduling algorithm can benefit the performance of wireless networks and improve the experience of mobile users. However, existing literature shows that it may not be the case, especially for TCP flows. According to early investigations, there are mainly two reasons that result in bad performance of TCP flows in wireless networks. One is the occurrence of out-of-order packets due to different delays in multiple paths. The other is the packet loss which is resulted from the limited bandwidth of wireless networks. To better exploit multipath scheduling for TCP flows, this paper presents a new scheduling algorithm named Adaptive Load Balancing Algorithm (ALBAM) to split traffic across multiple wireless links within the ISP infrastructure. Targeting at solving the two adverse impacts on TCP flows, ALBAM develops two techniques. Firstly, ALBAM takes advantage of the bursty nature of TCP flows and performs scheduling at the flowlet granularity where the packet interval is large enough to compensate for the different path delays. Secondly, ALBAM develops a Packet Number Estimation Algorithm (PNEA) to predict the buffer usage in each path. With PNEA, ALBAM can prevent buffer overflow and schedule the TCP flow to a less congested path before it suffers packet loss. Simulations show that ALBAM can provide better performance to TCP connections than its other counterparts. 相似文献
95.
Dinesh Kalyanasundaram Shinnosuke Inoue Jong-Hoon Kim Hyun-Boo Lee Zenko Kawabata Woon-Hong Yeo Gerard A. Cangelosi Kieseok Oh Dayong Gao Kyong-Hoon Lee Jae-Hyun Chung 《Microfluidics and nanofluidics》2012,13(2):217-225
Simple, high-yield concentration of DNA is important for high-throughput genetic analysis and disease diagnosis. Glass-based microfilters are popular but the process requires centrifugation steps with cumbersome chemical processes. As an alternative, a concentration method using an electric field has been explored previously, but with limited efficiency. In this paper, electric field-induced concentration and capture of DNA are studied by using high-aspect-ratio microtips coated with a gold layer. The microtips are immersed longitudinally into a solution of 100???L containing ??-phage DNA. After DNA concentration using an electric field, the microtips are withdrawn from the solution. Under AC- and biased AC fields, DNA is concentrated by electrophoresis (EP), dielectrophoresis (DEP), and electroosmotic flow (EOF). To reduce capillary effects in the withdrawal process, the microtips are coated with positively charged poly-l-lysine (PLL). The pattern of captured DNA is analyzed by fluorescence microscopy. DEP attracts DNA molecules at the edges of microtips, where the highest gradient of electric field exists. EP attracts DNA onto the surface of microtips following the vectors of an electric field. EOF generates vortexes that deliver DNA onto microtips. Using this method, 85% of DNA is captured on the PLL-coated microtips after three sequential captures. The concentration mechanism can potentially facilitate rapid and simple preparation of DNA for downstream analysis. 相似文献
96.
Chee -Keng Yap 《Algorithmica》1988,3(1-4):279-288
We give a parallel method for triangulating a simple polygon by two (parallel) calls to the trapezoidal map computation. The method is simpler and more elegant than previous methods. Along the way we obtain an interesting partition of one-sided monotone polygons. Using the best-known trapezoidal map algorithm, ours run in timeO(logn) usingO(n) CREW PRAM processors. 相似文献
97.
Shin K. Berry John W. Gramshaw 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1986,182(3):219-223
Summary The volatile compounds from the Maillard reaction in the glucose - glutamic acid system were analysed by combined gas chromatography - mass spectrometry. Of the 50 peaks detected, 42 components comprising 2 acids, 2 alcohols, 5 carbonyls, 2 esters, 4 lactones, 17 furans, 4 pyrazines and 3 pyrroles were identified, four of which tentatively. Decadien 2,4-al, 2-n-pentyl furoate, 2-(2-fury()-pyrazine. -nonalactone, 2-(2-fury()-5- or 6-methylpyrazine were previously not reported to occur in heated sugar - amino acid browning systems. The new compound, 5-formyloxymethyl-2-furfural has apparently not yet been recorded in the chemical literature.The compound 5-acetoxymethyl-2-furfural had an aroma close to that of bread whereas 5-formyloxymethyl-2-furfural exhibited a very faint sweet burnt aroma.
Taken in part from the Ph. D. thesis of the Senior Author 相似文献
Einige neue flüchtige Verbindungen aus der nicht-enzymatischen Bräunungsreaktion des Glucose-Glutaminsäure-Systems
Zusammenfassung Die flüchtigen Verbindungen aus der Maillardreaktion des Glucose-Glutaminsäure-Systems wurde mit Hilfe der Gaschromatographie/Massenspektrometrie analysiert. Von den 50 nachgewiesenen Peaks wurden 42 identifiziert: 2 Säuren, 2 Alkohole, 5 Carbonyle, 2 Ester, 4 Lactone, 17 Furane, 4 Pyrazine, 3 Pyrrole und 4 weitere provisorisch. Deca-2,4-dienal, 2-n-Pentylfluorat, 2-(2-Furyl)-pyrazin, -Nonalacton, 2-(2-Furyl)-5 oder -6-Methylpyrazin wurden bisher nicht in dem erhitzten Zucker-Aminosäuren-Bräunungssystem registriert. Die neue Verbindung 5-Formyloxymethyl-2-furfural ist anscheinend noch nicht in der chemischen Literatur festgestellt worden. Die Verbindung 5-Acetoxymethyl-2-furfural hat an ein Brot erinnerndes Aroma, während die 5-Formyloxymethyl-2-furfural-Verbindung ein sehr schwaches süßlich-verbranntes Aroma aufweist.
Taken in part from the Ph. D. thesis of the Senior Author 相似文献
98.
Amirah Mohammad-Sidik Jian Sun Ryoung Shin Zhizhong Song Youzheng Ning Elsa Matthus Katie A. Wilkins Julia M. Davies 《International journal of molecular sciences》2021,22(2)
Extracellular ATP (eATP) has long been established in animals as an important signalling molecule but this is less understood in plants. The identification of Arabidopsis thaliana DORN1 (Does Not Respond to Nucleotides) as the first plant eATP receptor has shown that it is fundamental to the elevation of cytosolic free Ca2+ ([Ca2+]cyt) as a possible second messenger. eATP causes other downstream responses such as increase in reactive oxygen species (ROS) and nitric oxide, plus changes in gene expression. The plasma membrane Ca2+ influx channels involved in eATP-induced [Ca2+]cyt increase remain unknown at the genetic level. Arabidopsis thaliana Annexin 1 has been found to mediate ROS-activated Ca2+ influx in root epidermis, consistent with its operating as a transport pathway. In this study, the loss of function Annexin 1 mutant was found to have impaired [Ca2+]cyt elevation in roots in response to eATP or eADP. Additionally, this annexin was implicated in modulating eATP-induced intracellular ROS accumulation in roots as well as expression of eATP-responsive genes. 相似文献
99.
100.
Manu Kumar Sang-Min Chung Ganuskh Enkhtaivan Rahul V. Patel Han-Seung Shin Bhupendra M. Mistry 《International journal of molecular sciences》2021,22(5)
In this study, we have introduced newly synthesized substituted benzothiazole based berberine derivatives that have been analyzed for their in vitro and in silico biological properties. The activity towards various kinds of influenza virus strains by employing the cytopathic effect (CPE) and sulforhodamine B (SRB) assay. Several berberine–benzothiazole derivatives (BBDs), such as BBD1, BBD3, BBD4, BBD5, BBD7, and BBD11, demonstrated interesting anti-influenza virus activity on influenza A viruses (A/PR/8/34, A/Vic/3/75) and influenza B viral (B/Lee/40, and B/Maryland/1/59) strain, respectively. Furthermore, by testing neuraminidase activity (NA) with the neuraminidase assay kit, it was identified that BBD7 has potent neuraminidase activity. The molecular docking analysis further suggests that the BBD1–BBD14 compounds’ antiviral activity may be because of interaction with residues of NA, and the same as in oseltamivir. 相似文献