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1.
The aim of our study was to analyze mitochondrial and endoplasmic reticulum (ER) gene expression profiles in subcutaneous (SAT) and epicardial (EAT) adipose tissue, skeletal muscle, and myocardium in patients with and without CAD undergoing elective cardiac surgery. Thirty-eight patients, 27 with (CAD group) and 11 without CAD (noCAD group), undergoing coronary artery bypass grafting and/or valvular surgery were included in the study. EAT, SAT, intercostal skeletal muscle, and right atrium tissue and blood samples were collected at the start and end of surgery; mRNA expression of selected mitochondrial and ER stress genes was assessed using qRT-PCR. The presence of CAD was associated with decreased mRNA expression of most of the investigated mitochondrial respiratory chain genes in EAT, while no such changes were seen in SAT or other tissues. In contrast, the expression of ER stress genes did not differ between the CAD and noCAD groups in almost any tissue. Cardiac surgery further augmented mitochondrial dysfunction in EAT. In our study, CAD was associated with decreased expression of mitochondrial, but not endoplasmic reticulum stress genes in EAT. These changes may contribute to the acceleration of coronary atherosclerosis.  相似文献   
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3.
Prospect theory postulates that the utility function is characterized by a kink (a point of non-differentiability) that distinguishes gains from losses. In this paper we present an algorithm that efficiently solves the linear version of the kinked-utility problem. First, we transform the non-differentiable kinked linear-utility problem into a higher dimensional, differentiable, linear program. Second, we introduce an efficient algorithm that solves the higher dimensional linear program in a smaller dimensional space. Third, we employ a numerical example to show that solving the problem with our algorithm is 15 times faster than solving the higher dimensional linear program using the interior point method of Mosek. Finally, we provide a direct link between the piece-wise linear programming problem and conditional value-at-risk, a downside risk measure.  相似文献   
4.
The lattice parameters of polycrystalline ZnO in mixtures of ZnO-Bi2O3 and their dependence on Bi2O3-concentration were determined. Simultaneously the influence of ZnO presence on the origin of various modifications of Bi2O3 was observed. On the grounds of the measured decrease of the elementary cell volume the supposition about the interaction of Zn-intersititals with overstoichiometric oxygen atoms in Bi2O3 was accepted. In accordance with this idea the changes of free carrier concentration of samples ZnO+5 mol% Bi2O3 in the dependence on annealing temperature were found.  相似文献   
5.
A ternary ordered variant of the skutterudite structure, the Co4Sn6Se6 compound, was prepared. Polycrystalline samples were prepared by a modified ceramic method. The electrical conductivity, the Seebeck coefficient and the thermal conductivity were measured over a temperature range of 300–800 K. The undoped Co4Sn6Se6 compound was of p-type electrical conductivity and had a band gap E g of approximately 0.6 eV. The influence of transition metal (Ni and Ru) doping on the thermoelectric properties was studied. While the thermal conductivity was significantly lowered both for the undoped Co4Sn6Se6 compound and for the doped compounds, as compared with the Co4Sb12 binary skutterudite, the calculated ZT values were improved only slightly.  相似文献   
6.
Chronopotentiometric stripping analysis (CSA) was used for selective determination of As(III) and As(V) in different oilseeds. After the optimization of experimental parameters an appropriate procedure for sample pretreatment was developed. A detection limit of 2 microg/dm3 for As(III) was obtained with an electrolysis time of 600 s. This method was used for arsenic determination in sunflower, pumpkin, and flax seed, as well as for soy flakes and almond.  相似文献   
7.
It was demonstrated that non-homopolymerizing derivatives of 6-caprolactam: 7-cyclohexyl-1-aza-2-cycloheptanone (I) and 7-isopropyl-5-methyl-1-aza-2-cycloheptanone (II) were polymerizing with 6-caprolactam under conditions of the socalled hydrolytic polymerization. With its increasing content in the initial reaction mixture the copolymerization rate, the equilibrium content of the copolymer, and the reduced viscosity decreased. Lactam (I) was a more reactive comonomer in comparison with lactam (II).  相似文献   
8.
The effects of the CCK(B) antagonists, CAM1028 and CI988 and a CCK(A) antagonist, CAM1481, were studied on the anxiety-related behaviour produced by withdrawal from chronic ethanol treatment, using the elevated plus maze. Cessation of chronic ethanol administration produced a profile, in both mice and rats, consistent with increase in anxiety-related behaviour. In mice, SC administration of CAM1028 or CI988 reduced the decrease in the time spent on the open arms, the number of entries into these arms and the increases in the latencies to first open arm entry, after withdrawal from the ethanol treatment. The increases in stretched attend postures and head dips from the closed arms and the central square seen during the withdrawal phase, were also decreased by the CCK(B) antagonists, but the decreases in the number of rears and in general activity were unaffected. The doses of CAM1028 and CI988 tested were 0.1 and 1 mg/kg; for some of the withdrawal-induced changes in behaviour only the 1 mg/kg dose was effective. In contrast, the CCK(A) antagonist, CAM1481, at the same doses, had little effect on the anxiety-related behaviour produced by withdrawal from chronic ethanol treatment, although it did decrease the changes in the number of rears and the head dipping behaviour. In rats, the majority of the changes produced by withdrawal from chronic ethanol treatment were decreased by CAM1028 at 1 mg/kg, although the decreases in open arm entries, rearing behaviour and in overall activity were unaffected. CAM1028, CI988 and CAM1481 had no effects on the behaviour of control mice or rats in the plus-maze. The results show that CCK(B) antagonists were effective in decreasing the majority of the anxiogenic effects of withdrawal from chronic ethanol treatment.  相似文献   
9.
Simple electroanalytical method for histamine determination based on its irreverse oxidation by a constant current on a thin film mercury electrode was developed in this work. Experimental parameters of chronopotentiometric analysis, such as concentration of the supporting electrolyte, initial potential and dissolution current were optimised. The optimal experimental parameters included an initial potential of −0.4 V and oxidation currents in the range from 3 to 30 μA in 0.02 mol/l sulphuric acid. After the optimisation of experimental parameters, the linear response was obtained in the range 2–90 mg/l of histamine with achieved detection limit of 1.31 mg/l of histamine. The method was applied for the determination of histamine in various types of cheese. Prior sample analysis the procedure for sample preparation was developed and included ultrasonically-assisted extraction and chromatographic separation on a thin layer. To our knowledge, histamine has never previously been determined on mercury electrodes nor by applying chronopotentiometric analysis, thus developed electroanalytical method represents an important contribution to electroanalytical practise. By applying the developed method it is possible to perform simple and fast cheese analysis. Furthermore, in comparison to competitive chromatographic techniques, chronopotentiometric method allows the analysis of foodstuffs under moderate price.  相似文献   
10.
The mechanism of oxygen and argon transfer into aqueous emulsions of n-alkans and of oleic acid was studied both theoretically and experimentally. An apparatus allowing to measure the coefficient of mass transfer from individual bubbles into the turbulent medium of either a single- or multi-phase liquid has been designed and constructed. The effect of the oil phase on the bubble-to-emulsion mass transfer coefficient was investigated. In o/w type emulsions (oil as the dispersed and water as the continuous phase) of n-alkans (the system with negative spreading coefficient) the mass transfer coefficient kLw is not affected by the content of the oil phase, and is equal to the coefficient of mass transfer into a pure aqueous phase. In the w/o type emulsion the kLw value increases proportionately to the volume fraction of n-alkans. In the oleic acid-in-water emulsion (the system with positive spreading coefficient) kLw initially decreases and then increases proportionately to the oil fraction. The initial decrease of kLw is attributed to surface activity effects of oleic acid. The data suggest that the mechanism of gas transfer to the emulsions is as follows: No direct contact between the oil and the gas phase exists in o/w type emulsions with negative spreading coefficient, and the transfer path is gas-water-oil. In w/o type emulsions (both with negative and positive spreading coefficient), however, there is a direct contact between the gas and both the continuous oil phase and the dispersed aqueous phase; there is a parallel transfer of gas to both the phases.  相似文献   
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