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441.
CRISPR/Cas has emerged as an excelle nt gene-editing technology and is used worldwide for research. The CRISPR library is an ideal tool for identifying essential genes and synthetic lethality targeted for cancer therapies in human cancers. Synthetic lethality is defined as multiple genetic abnormalities that, when present individually, do not affect function or survival, but when present together, are lethal. Recently, many CRISPR libraries are available, and the latest libraries are more accurate and can be applied to few cells. However, it is easier to efficiently search for cancer targets with their own screenings by effectively using databases of CRISPR screenings, such as Depmap portal, PICKLES (Pooled In-Vitro CRISPR Knockout Library Essentiality Screens), iCSDB, Project Score database, and CRISP-view. This review will suggest recent optimal CRISPR libraries and effective databases for Novel Approaches in the Discovery and Design of Targeted Therapies.  相似文献   
442.
We achieved separate detection of the components of 10 ppm of a benzene, toluene, and o-xylene mixture gas by using mesoporous silica powder incorporated in our microfluidic device. The device consists of concentration and detection cells formed of 3 cm x 1 cm Pyrex plates. We first introduced the mixture gas into the concentration cell where it was adsorbed on an adsorbent in a channel formed in the cell. We then raised the temperature using a thin-film heater and introduced the desorbed gas into the detection cell. Here, we measured the changes in the absorption spectra of the mixture gas in the detection cell. We found that the mixture ratio of the compounds in the desorbed gas varies with time because the thermal desorption property of each compound is different from that of the adsorbent. We analyzed the thermal desorption mechanism by comparing two types of silica adsorbents with different pore structures. We found that an adsorbent that has pores with a periodic and uniform nanosized column shape provides better component separation. We concluded that the uniform pore structure might cause the adsorbate molecules to exhibit a homogeneous adsorption state thus revealing the desorption properties of the gas more clearly.  相似文献   
443.
Glass fiber-reinforced polymer (GFRP) bridge decks suffering frequent cyclic loading of heavy wheels require relatively thick pultruded composites. To examine the behavior of 12 mm thick pultruded GFRP plates containing surface layers and to study the influence of surface damage, which may be present on such decks, static and fatigue tensile tests were carried out. Severe indentation yielded not only visible damage, but also an invisible damage in the unidirectional layer. Loss of cross section area due to both damages affected the static ultimate loads. Fatigue cracks were found around higher stress concentrations on the surface layer as early as approximately 10% of the total fatigue life. These initial cracks, however, barely affected the fatigue life because delamination of the surface layers prevented the cracks from propagating. The invisible shear crack due to indentation barely affected the fatigue life since earlier splitting between initially damaged and undamaged fibers mitigated the crack propagation.  相似文献   
444.
The compositions and microstructures, thermolyses, and sensitivities of 3,3-bis(azidomethyl)oxetane (BAMO) copolymers with 3-nitratomethyl-3-methyloxetane (NMMO) were characterized. The molar ratios of monomers fed in the copolymerizations were: BAMO/NMMO = 8/2, 7/3, and 6/4. The observed compositions were 81/19, 68/32, and 60/40, respectively. The relative compositions of trade microstructures were also exactly the same as theoretical values. The copolymerization of BAMO with NMMO behaved like an ideal system in the sense that the copolymer has approximately the same composition as the monomer fed. The microstructures of copolymers were also randomly arranged. Poly BAMO showed side chain decomposition in the initial stage of the thermolysis, on the other hand, backbone decomposition controlled the thermolysis of poly NMMO. The BAMO units and the NMMO units appeared to decompose more or less independently of one another and retained their individual decomposition characteristics despite being copolymerized. However, the heat generated by the NMMO decomposition, which occurred at 40°C lower than that of BAMO. activated the reaction of BAMO. Poly B/N(7/3) showed very interesting characteristics in sensitivities, mechanical properties, and the heat of decomposition.  相似文献   
445.
The FA composition in the sn-2 position of TAG is routinely determined after porcine pancreatic lipase hydrolysis. However, the content of saturated FA increased when a pancreatic lipase preparation with higher specific activity was used. Lipase from Rhizopus delemar was selected as a potential replacement lipase for the following reasons: (i) The FA specificity is nearly equivalent in hydrolysis activity toward FA such as lauric, myristic, palmitic, palmitoleic, stearic, oleic, linoleic, and α-linolenic acids; and (ii) lipase from R. delemar hydrolyzes fatty acyl residues at the sn-1,3 positions of TAG. Acyl migration products were present at less than 0.8% in lipase hydrolysates containing 6–14% of sn-2 MAG. A reproducibility CV of less than 5% was obtained in a collaborative study in which the compositions of the main FA at the sn-2 position in olive oil were determined using lipase from R. delemar. This article was presented in part at the Biocatalysis Symposium, 94th AOCS Annual Meeting & Expo, Kansas City, Missouri, May 2003.  相似文献   
446.
Decreased expression of diacylglycerol kinase (DGK) δ in skeletal muscles attenuates glucose uptake and is closely related to the pathogenesis of type 2 diabetes. Therefore, up‐regulation of DGKδ expression is thought to protect and improve glucose homoeostasis in type 2 diabetes. We recently determined that myristic acid (14:0), but not palmitic (16:0) or stearic (18:0) acid, significantly increased DGKδ2 protein expression in mouse C2C12 myotubes. In the current study, we analyzed whether myristic acid indeed enhances glucose uptake in C2C12 myotubes. We observed that myristic acid caused ~1.4‐fold increase in insulin‐independent glucose uptake. However, palmitic and stearic acids failed to enhance glucose uptake. DGKδ‐specific siRNA decreased myristic acid‐dependent increase of glucose uptake. Moreover, overexpression of DGKδ2 enhanced glucose uptake in C2C12 cells in the absence of myristic acid treatment. Taken together, these results strongly suggest that myristic acid enhances basal glucose uptake in myotubes in a DGKδ2 expression‐dependent manner.  相似文献   
447.
Complex hydrides for hydrogen storage   总被引:5,自引:0,他引:5  
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448.
Mg-Al layered double hydroxide intercalated with CO_3~(2-)(CO_3·Mg-Al LDH) is effective for treating HCl exhaust gas.HCl reacts with CO_3~(2-) in CO_3·Mg-Al LDH, resulting in the formation of Cl·Mg-Al LDH.We propose that CO_2 can be used for the desorption of Cl~-from Cl·Mg-Al LDH to regenerate CO_3·Mg-Al LDH.Herein,we studied the desorption of a from CI-Mg-Al LDH by adding water to Cl·Mg-Al LDH and blowing CO_2 into it.We also analyzed the effects of temperature and water addition speed on the desorption of CI~-from Cl·Mg-Al LDH.Our results show that the added water adhered to CI·Mg-Al LDH and that CO_2 in the gaseous phase was dissolved in this adhered water,thus generating CO_3~(2-).Therefore,anion exchange occurred between CO_3~(2-) and Cl~-in the Cl·Mg-Al LDH,thus desorbing Cl~-.  相似文献   
449.
Glutathione S-transferase π (GSTP1-1) is overexpressed in many types of cancer and is involved in drug resistance. Therefore, GSTP1-1 is an important target in cancer therapy, and many GST inhibitors have been reported. We had previously developed an irreversible inhibitor, GS-ESF, as an effective GST inhibitor; however, its cellular permeability was too low for it to be used in inhibiting intracellular GST. We have now developed new irreversible inhibitors by introducing sulfonyl fluoride (SF) into chloronitrobenzene (CNB). The mechanism of action was revealed to be that CNBSF first reacts with glutathione (GSH) through an aromatic substitution in the cell, then the sulfonyl group on the GSH conjugate with CNBSF reacts with Tyr108 of GST to form a sulfonyl ester bond. Our new inhibitor irreversible inhibited GSTP1-1 both in vitro and in cellulo with a long duration of action.  相似文献   
450.
Filled rubbers have a long history in rubber technology. Filler morphology in the rubber matrix significantly influences the performance of filled rubber products. Therefore, we have to achieve a certain morphology of filler in the rubbery matrix in order to enjoy good reinforcement. However, it has not been sufficiently known what kind of morphology is necessary for the reinforcement, because preparations of adequate models for the characterization of filler morphology have been difficult. The in situ silica filling of the rubber matrix can be modeled for the preparations. In this paper, the characteristic features of in situ silica generated in diene rubbers are reviewed, citing recent reports. Two important models are presented. One is a homogeneous silica filling in situ, producing soft rubber nanocomposites. The other is the formation of an in situ silica filler network, creating stiff rubber nanocomposites. The controlled in situ silica filling is useful to evaluate the reinforcement effect of filler in a rubber matrix. © 2016 Society of Chemical Industry  相似文献   
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