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81.
Hydrothermally stable Al-MCM-48 with variety of Si/Al ratios and Al-MCM-41 with tunable pore sizes were successfully obtained from pre-heated aluminosilicate gel precursor. They showed the higher acid strength and hydrothermal stability comparing with conventional ones. Thus, this synthetic strategy offers a straightforward and convenient access to mesoporous aluminosilicates with zeolite-like acidity and stability.  相似文献   
82.
A near-infrared (NIR) and mid-infrared (mid-IR) dual-region spectrometer having two immersion probes, a transmission probe for NIR, and an attenuated total reflection (ATR) probe for mid-IR has been developed for highly reliable process monitoring and deep process understanding. This spectrometer facilitates sequential acquisition of both NIR (10,000-4000 cm(-1)) and mid-IR (5000-1200 cm(-1)) spectra by switching the light path leading to the probes without the need for probe replacement. The use of a single light source and a single beam splitter enables achievement of a permanent alignment of the optical system and sequential data acquisition. The transmission NIR and ATR mid-IR probes designed and developed in the present study facilitate the acquisition of NIR/mid-IR spectra with optimized absorption intensities in both regions by simply placing the probes into a sample solution. The performance of the developed spectrometer was demonstrated in monitoring the ethanol fermentation process. NIR/mid-IR spectra of the fermentation solution with multiplicative scatter correction (MSC) represent the relative changes in the concentrations of glucose and ethanol in both regions. Principal component analysis (PCA) was performed on the MSC-treated spectra in the regions 6300-5650 cm(-1), 4850-4300 cm(-1), and 3500-2880 cm(-1) to detect the end-point of the fermentation as an example of process monitoring. For all the regions, the score plot of the first principal component (PC) indicates that the fermentation progresses with the fermentation time and stops after 210 minutes and thus the end-point of the fermentation exists at around 210 minutes. The loading plot indicates that all of the first PCs are the relative changes in the concentrations of glucose and ethanol. This result reveals that the same chemical changes are observed in both transmission NIR and ATR mid-IR spectra. Multiple and simultaneous analysis was also performed, and intensity change in light scattering relating the growth of yeasts was monitored by the NIR spectra.  相似文献   
83.
The total estrogenic activity of the wastewater from a swine farm in Japan was quantitatively characterized, and the compounds responsible for the estrogenic activity were identified and quantified. The wastewater treatment process consisted of a series of an up-flow anaerobic sludge blanket (UASB) and a trickling filter. Samples were collected at each treatment step, and the total estrogenic activity was determined by use of an in vitro gene expression assay (MVLN; MCF-7 human breast cancer cell stably transfected with the pVit-tk-LUC receptor plasmid). Individual estrogenic compounds were identified and quantified using liquid chromatography-mass spectrometry (LC/MS) and liquid chromatography-tandem mass spectrometry (LC/ MS/MS). To further identify the compounds contributing to the estrogenic activity in the wastewater, the sample extracts were fractionated into 12 fractions (fractions 1-12) by HPLC. The rate of removal of estrogenic activity between the effluent and the influent was greater than 97%. The trickling filter removed the majority of the estrogenic activity. The removal rates of specific estrogenic compounds ranged from 44 to 99%. Estrogenic activity was detected mainly in the fractions containing estrone (El), 17beta-estradiol (betaE2), 17alpha-estradiol (alpha E2), estriol (E3), bisphenol A (alphaPA), and equol (EQ0). The ratios of betaE2-EQc (betaE2 equivalents derived from chemical analysis) to betaE2-EQB (betaE2 equivalent derived from bioassay) in the 12 fractions collectively were contributed by El (17-30%), betaE2 (23-30%), acE2 (<1%), E3 (1-2%), BPA (<1%), and EQO (2-3%) in the influent and El (16-37%), PE2 (<1-7%), alphaE2 (<1%), E3 (<1-3%), BPA (<1%), and EQO (<1%) in the effluent. The compounds responsible for most of the estrogenic activity measured in the bioassay were natural estrogens such as El and betaE2.  相似文献   
84.
This paper describes a triangular surface charge method (TSCM) called (3,1)‐TSCM, which uses curved surface elements for calculating electric fields in composite dielectrics. The boundary element utilizes a cubic shape function with nine degrees of freedom and a linear function for representing the charge density on its surface. Conventional SCMs, including the (3,1)‐TSCM, show a very large relative error in the composite dielectrics where the permittivity is much higher in one medium than in the other. A modified method called the β method can suppress such relative errors, which expresses electric fields by surface charges without subtraction causing large relative errors. We have applied the β method to the (3,1)‐TSCM and calculated electric fields for a spherical dielectric under a uniform field. The calculated results show that the (3,1)‐TSCM improves the accuracy of the electric field by more than one order compared with the method using flat surface elements with constant charge density on each element. Furthermore, the β method completely suppresses the divergence of relative errors even when the ratio of the permittivity of two media reaches 1010. © 2001 Scripta Technica, Electr Eng Jpn, 136(1): 1–8, 2001  相似文献   
85.
Summary Dehalogenative polycondensation of 1,2-dibromoethylene, trans-1,2-dichloroethylene, and cis-1,2-dichloroethylene with a Ni(0) complex gave a black polymer whose IR spectrum essentially agreed with that of trans-polyacetylene. Suzuki-Miyaura coupling between 1,2-dibromoethylene and vinylene diboronic compounds was applied to synthesis of -conjugated polymers.  相似文献   
86.
The adzuki bean borer, Ostrinia scapulalis, has distinct genetic variation in the blend of two sex pheromone components, (E)- and (Z)-11-tetradecenyl acetates. This variation is largely controlled by a single autosomal locus with two alleles, E and Z. E-type (EE) females produce a pheromone with a mean E:Z ratio at 99:1 whereas Z-type (ZZ) and I-type (ZE) produce pheromones with mean of 3:97 and 64:36, respectively. Interestingly, in many natural populations of O. scapulalis in Japan, this pheromone polymorphism appears to be stably maintained. We tried to predict the changes in relative abundance of each pheromone type by estimating the pheromone production genotype of wild females and their male mates. The pheromone titer in the wild, mated females was increased without changing the blend ratio by an injection of a peptide with pheromone biosynthesis activating activity (TKYFSPRL-NH2). The frequencies of E-, I-, and Z-types at Matsudo were 15, 52, and 33%, respectively, and did not deviate from the Hardy-Weinberg expectations. The estimated mating patterns were concordant with the assumption that no assortative mating was occurring in this population, and this is suggested as a cause of sustained polymorphism at Matsudo.  相似文献   
87.
Atomic-resolution high-resolution high-voltage transmission electron microscopy was applied to the chemical structure analysis of silicon carbide. Each atomic column was imaged in dark contrast. Silicon and carbon were distinguished from each other in image contrast, i.e. silicon appeared in darker contrast and carbon appeared in lighter contrast. For the projected potential image to provide chemical structure information, it was estimated that the specimen thickness needs to be less than 5 nm. The precise atomic columnar site was determined by using the maximum entropy method.  相似文献   
88.
As human on-off decisions are the basic problems in our human lives, the analysis of human on-off decision making is an interesting topic. The procedures of qualified human decision making include many intuitive factors which have been acquired from previous valuable experience and gained through learning, but they may not be easily understood by others within a short period. By the use of a database of causes and decisions made by qualified experts for an objective event, human decision making for that event can be realizable artificially. This paper investigates a general method for realizing artificial human on-off decision making based on the conditional probability of the database. As on-off decision making is a discrete event and the causes for that decision making are continuous events, a mathematical treatment of a Dirac delta function in a probability density function is required to derive the conditional probability for the decision making. Several examples of artificial human decision making by the proposed method were demonstrated, and the results obtained showed good agreement with those of human experts in the respective fields. This work was presented, in part, at the Fourth International Symposium on Artifical Life and Robotics, Oita, Japan, January 19–22, 1999  相似文献   
89.
The measurement of accumulated surface charge for thick specimens requires multipoint probe outputs to establish the inverse calculation for the determination of an unknown charge distribution. Until now, studies on the various errors associated with the measurement have been conducted only for simplified arrangements mainly in axisymmetric geometry where the charged surface is parallel to the ground. We have numerically analyzed a model measurement set-up more comparable to practical conditions by a highly efficient surface charge method. We have studied the effect of probe position, the induction from charge existing not directly beneath the (probe) sensor and the difference in matrix components computed by two numerical methods. In particular, we have studied the accuracy of the reconstructed charge distributions by numerical simulations of the inverse calculation. It has been shown that the assumed measurement errors make much larger differences in the reconstructed charge distributions, although the influence depends considerably on the assumed charge distribution. Reducing the condition number of the matrix improves the accuracy of the inverse calculation for uniform and linearly changing charge distributions  相似文献   
90.
To achieve higher reconfigurability of an assembly line, quick plug-in and plug-out of devices such as robots is essential. When a new device is installed into the assembly line, calibration should be made. This research deals with an automated calibration system of relative position/orientation based on the Direct Linear Transformation method using two CCD cameras. The cameras are freely positioned, and then a set of motions is commanded to each manipulator. By detecting the motion with the cameras, the relative position of the two robots is obtained. The resultant accuracy is 0.16 mm rms at the best.  相似文献   
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