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141.
The combined use of plants and associated microorganisms has great potential for cleaning up soils contaminated with petroleum hydrocarbons. Apart from environmental conditions the physicochemical properties of the soil are the main factors influencing the survival and activity of an inoculated strain as well as the growth of plants. This study examined the effect of different soil types (sandy, loamy sand and loam) on the survival, gene abundance and catabolic gene expression of two inoculated strains (Pseudomonas sp. strain ITRI53 and Pantoea sp. strain BTRH79) in the rhizosphere and shoot interior of Italian ryegrass vegetated in diesel contaminated soils. High colonization, gene abundance and expression in loamy soils were observed. By contrast, low colonization, gene abundance and absence of gene expression in sandy soil were found. The highest levels of genes expression and hydrocarbon degradation were seen in loamy soil that had been inoculated with BTRH79 and were significantly higher compared to those in other soils. A positive correlation was observed between gene expression and hydrocarbon degradation indicating that catabolic gene expression is necessary for contaminant degradation. These results suggest that soil type influences the bacterial colonization and microbial activities and subsequently the efficiency of contaminant degradation.  相似文献   
142.
143.
End‐stage renal disease is associated with dismal long‐term survival in general. Home hemodialysis (HHD) has been advocated as a modality affirming better quality of life and longer survival. We report a 62‐year‐old Caucasian female with end‐stage renal disease who has been exclusively on HHD for a total of 45 years, utilizing various platforms over the years. She has been one of the first home dialysis patients of the founding father of renal dialysis in the state of Mississippi, John D. Bower and cared by him throughout his career. Throughout this period, her life bore witness to the evolving technology of dialysis accesses, platforms, and evolution of HHD in its entirety. After review of the literature, we find that the longest vintage time on HHD documented to date was around 35 years. This extraordinary longevity bears testimony to the extraordinary self‐motivation of the patient, the dedication of her providers and the true potential of HHD in motivated subjects.  相似文献   
144.
The pay-TV industry seeks to extend its reach to portable display devices. At the same time, it seeks to ensure a horizontal market by making interoperable the Conditional Access Systems (CASs) employed to protect content. To achieve interoperability for such devices, this paper proposes a form of selective encryption for video that allows simultaneous distribution of a small percentage of video data on a per-CAS basis, allowing sharing of the unencrypted video between the CASs. The bitrate overhead for each additional CAS enabled is found to be on average 7.41 %, whereas the computational overhead amounts to no more than 40 ms for the benchmark sequences tested. Adaptation of CAS to transparent encryption of scalable video is also demonstrated in this paper.  相似文献   
145.
An ultrafine-grained(UFG) low-carbon medium-manganese steel was fabricated by the heavily warm rolling(HWR) and subsequent quenching, and the effects of annealing temperatures on microstructure and mechanical properties of the UFG HWRed steel were investigated. The results show that the HWRed steel exhibits simultaneous improvements in strength,uniform elongation and work hardening, which is mainly attributed to the refinement of martensitic microstructures. The HWRed steels comprise only a-phase when annealing at lower temperatures below to 550 °C and at higher temperatures above to 700 °C. Whereas, UFG c-austenite is formed by reverse transformation when the HWRed steel was annealed at intermediate temperatures from 550 to 700 °C and the volume fraction increases with increasing annealing temperatures,consequently resulting in a dramatic increase in ductility of the annealed HWRed steels. It was found that the transformed UFG austenite and ferrite remained ~500 nm and ~800 nm in size when the HWRed steel was annealed at 650 and700 °C for 1 h, respectively, showing an excellent thermal stability. Moreover, the HWRed steel annealed at 650 °C exhibits high strength-ductility combinations with a yield strength of 906 MPa, ultimate tensile strength(UTS) of1011 MPa, total elongation(TEL) of 51% and product of strength and elongation(PSE: UTS 9 TEL) of 52 GPa%. It is believed that these excellent comprehensive mechanical properties are closely associated with the UFG austenite formation by reverse transformation and principally attributed to the transformation-induced plasticity(TRIP) effect.  相似文献   
146.
Multimedia Tools and Applications - Social media platforms such as Twitter, Facebook, and YouTube have unique architecture, norms, and culture. These platforms are valuable sources of...  相似文献   
147.
The objective of this study was to quantify changes in soybean seed quality characteristics in response to indigenous Bradyrhizobium inoculation and N fertilization applied under field conditions during the years 2009 and 2010. Seven indigenous Bradyrhizobium isolates were isolated from the different locations under the foothills of great Himalayas Rawalakot Kashmir, Pakistan. The field isolates were compared to a reference strain (exotic) TAL102, three N fertilizer rates and to an un‐inoculated control. The seed oil content, fatty acid composition, seed N, P and K concentration and seed N, P and K uptake were quantified. Bradyrhizobium inoculation and N fertilization significantly increased oil content compared to the un‐inoculated control. The seed oil content varied between 16.2 and 21.5 %, highest in the seeds treated with indigenous Bradyrhizobium strains NR22, NR25 and NR35, and mainly composed of linoleic acid (47 %), and oleic acid (24 %). Inoculation and N fertilization both decreased the saturated fatty acids (palmitic and stearic) and increased unsaturated fatty acids (linoleic acid and oleic acid). The mineral nutrient content of N, P, and K and their accumulation in seed increased by 2–3‐fold compared to the corresponding control. Indigenous Bradyrhizobium strains were able to generate the highest values for seed oil content (NR22, NR25, and NR35), unsaturated fatty acids, i.e. linoleic acid and oleic acid (NR25, and NR35) and N, P and K uptake (NR20, and NR22). There were noticeable differences among the treatments in terms of essential fatty acid, oil, and mineral nutrient content. The study demonstrates the potential benefits of using indigenous Bradyrhizobium strains in order to achieve high quality soybean seeds that can be used as a balanced health product.  相似文献   
148.
Colletotrichum higginsianum is an important hemibiotrophic plant pathogen that causes crucifer anthracnose worldwide. To date, some hexose transporters have been identified in fungi. However, the functions of hexose transporters in virulence are not clear in hemibiotrophic phytopathogens. In this study, we identified and characterized a new hexose transporter gene named ChHxt6 from a T-DNA insertion pathogenicity-deficient mutant G256 in C. higginsianum. Expression profiling analysis revealed that six ChHxt genes, ChHxt1 to ChHxt6, exhibited specific expression patterns in different infection phases of C. higginsianum. The ChHxt1 to ChHxt6 were separately deleted using the principle of homologous recombination. ChHxt1 to ChHxt6 deletion mutants grew normally on PDA plates, but only the virulence of ChHxt4 and ChHxt6 deletion mutants was reduced. ChHxt4 was required for fungal infection in both biotrophic and necrotrophic stages, while ChHxt6 was important for formation of necrotrophic hyphae during infection. In addition, ChHxts were functional in uptake of different hexoses, but only ChHxt6-expressing cells could grow on all five hexoses, indicating that the ChHxt6 was a central hexose transporter and crucial for hexose uptake. Site-directed mutation of T169S and P221L positions revealed that these two positions were necessary for hexose transport, whereas only the mutation Thr169 caused reduced virulence and defect in formation of necrotrophic hyphae. Taken together, ChHxt6 might regulate fungal virulence by modulating the utilization of hexose.  相似文献   
149.
本文介绍了直流电机、无刷电机、交流感应电机的差异及其子系统,深入分析了电流监测与测量、温度检测子系统以及电机速度、位置、运动检测系统.  相似文献   
150.
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