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991.
Two‐dimensional nanowaves with long‐range order are fabricated by exploiting swelling‐induced buckling of one‐dimensional (1D) nanowalls with nanofibers formed in‐between during holographic lithography of the negative‐tone photoresist SU‐8. The 1D film goes through a constrained swelling in the development stage, and becomes buckled above the critical threshold. The degree of lateral undulation can be controlled by tuning the pattern aspect ratio (height/width) and exposure dosage. At a high aspect ratio (e.g., 6) and a high exposure dosage, nanofibers (30–50 nm in diameter) are formed between the nanowalls as a result of overlapping of low crosslinking density regions. By comparing experimental results with finite‐element analysis, the buckling mechanism is investigated, which confirms that the nanofibers prevent the deformed nanowalls from recovery to their original state, thus, leading to long‐range ordered two‐dimensional (2D) wavy structures. The film with nanowaves show weaker reflecting color under an ambient light and lower transmittance compared to the straight nanowalls. Using double exposure through a photomask, patterns consisting of both nanowaves and nanowalls for optical display are created.  相似文献   
992.
During the EPC (expendable pattern casting) process, one of the essential requirements is to prevent pattern distortion duringsand filling and compaction. A new method which vibrates the system in a two-dimensional circular mode has been appliedto the EPC process. The molding properties of unbonded sand obtained by this new vibration mode are investigated andcompared with those in the one-dimensional vertical mode. For adequate compaction of sand. the circular vibration mode ismore effective than the vertical mode. Sand became more fluidized by the circular vibration and the particle pressure coefficientwas close to unity The particle pressure coefficient, which is defined as the ratio of horizontal to vertical sand pressure, isresponsible for the effectiveness of sand filling.  相似文献   
993.
Melon (Cucumis melo L.) is an economically important horticultural crop with abundant morphological and genetic variability. Complex genetic variations exist even among melon varieties and remain unclear to date. Therefore, unraveling the genetic variability among the three different melon varieties, muskmelon (C. melo subsp. melo), makuwa (C. melo L. var. makuwa), and cantaloupes (C. melo subsp. melo var. cantalupensis), could provide a basis for evolutionary research. In this study, we attempted a systematic approach with genotyping-by-sequencing (GBS)-derived single nucleotide polymorphisms (SNPs) to reveal the genetic structure and diversity, haplotype differences, and marker-based varieties differentiation. A total of 6406 GBS-derived SNPs were selected for the diversity analysis, in which the muskmelon varieties showed higher heterozygote SNPs. Linkage disequilibrium (LD) decay varied significantly among the three melon varieties, in which more rapid LD decay was observed in muskmelon (r2 = 0.25) varieties. The Bayesian phylogenetic tree provided the intraspecific relationships among the three melon varieties that formed, as expected, individual clusters exhibiting the greatest genetic distance based on the posterior probability. The haplotype analysis also supported the phylogeny result by generating three major networks for 48 haplotypes. Further investigation for varieties discrimination allowed us to detect a total of 52 SNP markers that discriminated muskmelon from makuwa varieties, of which two SNPs were converted into cleaved amplified polymorphic sequence markers for practical use. In addition to these markers, the genome-wide association study identified two SNPs located in the genes on chromosome 6, which were significantly associated with the phenotypic traits of melon seed. This study demonstrated that a systematic approach using GBS-derived SNPs could serve to efficiently classify and manage the melon varieties in the genebank.  相似文献   
994.
In this study, we demonstrate a simple method for the preparation of Li[Li0.2Ni0.16Mn0.56Co0.08]O2 particle using surfactants. Hydroxypropyl cellulose (HPC), gelatin, and sucrose were successfully used to decrease particle size and increase surface area of the Li[Li0.2Ni0.16Mn0.56Co0.08]O2 powders, meaning that the surfactants effectively dispersed the particles. There was no phase change due to the use of surfactants, however, some surfactants affected the crystallinity of the powders. The samples prepared using surfactants demonstrated effectively enhanced capacities and some surfactants, such as HPC, also improved rate capabilities by increasing surface area. However, increased surface area was also found to lead to the deterioration of cyclic performance due to the activation of unwanted side reactions between electrode and electrolyte. Nevertheless, the sample prepared using HPC showed better cyclic performance than the pristine sample. This may be attributed to its enhanced crystallinity. In contrast, the sample prepared using gelatin showed inferior cyclic performance to the pristine sample due to low crystallinity.  相似文献   
995.
996.
Product selectivity control for the synthesis of imidoylindoles and 4‐alkylidenedihydroquinazolines from N‐imidoyl‐o‐alkynylanilines via silver triflate‐catalyzed cycloisomerization or tetrabutylammonium fluoride‐promoted cyclization is described. The product selectivity depends mainly on the catalyst/promoter used, and on the substituents on the alkyne and amidine functions of the substrates.

  相似文献   

997.
To meet the demand of improved comfort for passengers, drive ability and standard in fuel economy; external variable displacement swash (wobble) plate type compressors are used in automobile air conditioning control system because of their low energy consumption and highly efficient characteristics. It controls the compressor displacement by increasing or reducing the swash plate angle. Solenoid operated electromagnetic control valve (ECV) in the compressor controls the air conditioning system by means of a pulse width modulation (PWM) input signal supplied from an external source (controller). The mechanism changes the swash plate angle by increasing or reducing the pressure of swash plate chamber using the ECV functions. The force (solenoid) for ECV operation is important as the force directly related to the movement of the internal feature i.e. mainly plunger of the ECV which is responsible for the amount of air/refrigerant flow that results the air conditioning control procedures with various pressure ports. The research paper highlights the improved theory and equation for calculating the working force (solenoid force) in ECV and experimental analysis of 3 (three) ECV samples followed by the comparison of theoretical and experimental force results.  相似文献   
998.
The performance of a reciprocating compressor in refrigeration and air-conditioning systems is influenced by the lubrication characteristics of the critical sliding components. Thus, the lubrication characteristics between the crankshaft and journal bearing have to be researched in order to improve the design and performance of a reciprocating compressor. Therefore, in this study, to enhance the EER (energy efficiency ratio) to reduce power consumption, and to improve the reliability of a reciprocating compressor for refrigeration and air conditioning systems, theoretical analysis of the friction characteristics between the crankshaft and journal bearing in a reciprocating compressor is studied. The results demonstrate that frictional characteristics are significantly influenced by the clearance between the crankshaft and journal bearing and the viscosity of the lubricating oil.  相似文献   
999.
Today’s wheel alignment inspection systems adopt various computer vision technologies. They, however, require high-end cameras, precisely manufactured targets, and massive calculation loops because they rely on low-dimensional data (two-dimensional images) for measuring higher-dimensional information (three-dimensional orientation) of the wheel posture. To improve this, a simple and inexpensive method using a consumer-grade depth-sensing camera such as Kinect is presented. It directly utilizes point clouds generated from its range image stream. All points within the region of interest (ROI) contain geometrical information of the wheel and are used for the alignment inspection procedures. Its feasibility is evaluated by examining whether the orientation could be aligned to the desired orientation using only the point cloud data. For verification, a one-wheel-based prototype was implemented, and comparative experiments with an existing commercial system were conducted. The experimental results showed that the proposed method provides satisfactory performance. We believe that the proposed method is feasible for practical usage and has a great potential to be an effective alternative to existing wheel alignment inspection methods.  相似文献   
1000.
A high band‐gap (~1.55 eV) chalcopyrite compound film (CuInGaS2) was synthesized by a precursor solution‐based coating method with an oxidation and a sulfurization heat treatment process. The film revealed two distinct morphologies: a densely packed bulk layer and a rough surface layer. We found that the rough surface is attributed to the formation of Ga deficient CuInGaS2 crystallites. Because of the high band‐gap optical property of the CuInGaS2 absorber film, a solar cell device with this film showed a relatively high open circuit voltage (~787 mV) with a power conversion efficiency of 8.28% under standard irradiation conditions. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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