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1.
M. Neupane J.L. Hutchison C.P. Van Tassell P.M. VanRaden 《Journal of dairy science》2021,104(8):8959-8965
Differences in breeds and sire lines suggest the presence of a genetic component for heifer livability (HLIV). Genomic evaluation for this trait can increase profitability and improve animal health and welfare. Evaluations for HLIV were examined from 3,362,499 calf data records from heifers of all breeds born from 2009 to 2016. Data were obtained from the national cooperator database maintained by the Council on Dairy Cattle Breeding (https://www.uscdcb.com/). The total number of deaths reported was 134,753 (4.01%), which included herds with death loss between 1.5 and 25.5%. Age at death was evaluated and ranged from >2 d of age until the heifer left the herd, with a maximum of 18 mo of age. Records were not included until 3 yr after the birthdate so that live status of contemporaries could be confirmed by a calving date for those animals. Deaths observed until 2 d after birth were considered to be a stillbirth rather than a failure of HLIV. The scale used for analysis of HLIV was 0 (died) or 100 (live), and the heritability estimate was 0.7% based on sire model with restricted maximum likelihood estimation. Genomic predicted transmitting abilities for Holstein ranged from ?1.6% to +1.6% with a standard deviation of 0.5%, and genomic predicted transmitting abilities for Jersey ranged from ?0.5% to +0.5% with a standard deviation of 0.2%. The mean overall death loss was about 4%. Reliabilities of genomic predictions for young animals averaged 46% for Holsteins and 30% for Jerseys, and corresponding traditional parent average reliabilities averaged 16% and 12%, respectively. Correlations of HLIV were 0.44 with productive life, 0.18 to 0.22 with yield traits, and 0.29 with early first calving on proven Holstein bulls. The HLIV trait had a favorable genetic trend in recent years, likely because of the indirect selection associated with the correlated traits. The trait HLIV should receive 1% of emphasis on the Lifetime Net Merit index, resulting in economic progress worth $50,000/yr. By encouraging more comprehensive recording on calf mortality, the reliabilities of genetic predictions could increase significantly. 相似文献
2.
Wireless Personal Communications - Faster development of smart electronic devices in recent years along with significant increase in demanding higher data rates has made cognitive radio networks... 相似文献
3.
The antioxidant vitamin E, -tocopherol, was tested as a candidate elicitor of alterable antiherbivory in soybean plants against cabbage looper larvae. Although a nonspecific antioxidant, vitamin E proved elicitory to the involved sulfhydryl-dependent receptor-energy transducer protein in soybean plasma membrane. Effects of -tocopherol were dependent on dosage, time, and space in the plant. The observed elicited effects were all decreases in herbivory. The best negative phytochemical correlate of looper feeding was the percentage of increased total HPLC peak area of extractables from elicited as compared to nonelicited leaves. Some specific compounds, e.g., glyceollins, were quantitatively major components of the total profile of secondary metabolites. 相似文献
4.
Brian Elder Rajan Neupane Eric Tokita Udayan Ghosh Samuel Hales Yong Lin Kong 《Advanced materials (Deerfield Beach, Fla.)》2020,32(17):1907142
The synergistic integration of nanomaterials with 3D printing technologies can enable the creation of architecture and devices with an unprecedented level of functional integration. In particular, a multiscale 3D printing approach can seamlessly interweave nanomaterials with diverse classes of materials to impart, program, or modulate a wide range of functional properties in an otherwise passive 3D printed object. However, achieving such multiscale integration is challenging as it requires the ability to pattern, organize, or assemble nanomaterials in a 3D printing process. This review highlights the latest advances in the integration of nanomaterials with 3D printing, achieved by leveraging mechanical, electrical, magnetic, optical, or thermal phenomena. Ultimately, it is envisioned that such approaches can enable the creation of multifunctional constructs and devices that cannot be fabricated with conventional manufacturing approaches. 相似文献
5.
6.
S. Neupane G. Kaganas R. Valenzuela L. Kumari X. W. Wang W. Z. Li 《Journal of Materials Science》2011,46(14):4803-4811
We report the synthesis of ruthenium dioxide (RuO2) nanostructures by thermal evaporation of RuO2 powder. RuO2 nanostructures of different shapes were synthesized at various concentration, flow rate, and pressure of oxygen. At a constant pressure of 3 torr of flowing oxygen, polygonal prism-like RuO2 nanorods with flat tips were grown at an O2 flow rate of 100 sccm; club-shaped nanorods with obelisk tip were formed at 300 and 600 sccm, and hollow rods with square tip were formed at 1800 sccm. A mixture of O2 and Ar at a total flow rate of 600 sccm led to the formation of short club-shaped nanorods indicating the suppression effect of Ar on the growth of nanorods. The pressure also had a significant effect on the formation of RuO2 nanostructures, at a fixed flow rate of 600 sccm of O2, a pressure of 3 torr resulted in the growth of club-shaped RuO2 nanorods, while high pressures of 380 and 760 torr resulted in the formation of both linear club-shaped and pine tree-like hierarchical RuO2 nanorods. X-ray diffraction and transmission electron microscopy analysis indicated the formation of tetragonal phase of RuO2 with high crystallinity. A density functional calculation on RuO2, RuO3, and RuO4 was performed to help to explain the experimental results. 相似文献
7.
A processing method called “accelerated mild anodization” is developed for preparation of high density and uniform nanoporous by anodization of aluminum. The idea is to use two different temperatures for both sides of sample in order to maintain mid level of current density during the anodization process. Here we have used high temperature for the back side of the sample in order to increase the current density while the electrolyte is kept at low temperature in the level of mild anodization. It is shown that not only the film growth is considerably fast, almost ten times faster than mild anodization, but also the anodization voltage is constant and anodization current variation is much less compared to hard anodization technique. Using oxalic acid, interpore distances of 89, 104, 117 and 130 nm were obtained for 35, 40, 45 and 50 V anodization voltages, respectively. It is found that the interpore distances are proportional to the anodization potential, almost same as that for the mild anodization. The porosity obtained tended to obey the same rule as that in mild anodization. This method is promising for industrial application due to short fabrication time as well as high-speed pore ordering. 相似文献
8.
Companies strive to minimise supply chain related risks during new product development as any glitch while developing new products can lead to considerable delay in product launch with severe financial implications. However, many organisations face difficulty in properly assessing the vulnerabilities of their globally dispersed supply chains during the product development stage as no suitable procedure for that purpose seems to be readily available in the literature. The present research is an attempt to fulfil this requirement. A step-by-step approach for supply chain risk assessment during new product development, involving group decision making, is suggested. This approach can use both numeric and linguistic data and helps in determining vulnerability scores for various sub-systems and for each supplier of the most vulnerable sub-system. This is followed by failure mode effect analysis (FMEA) which helps prioritise failure modes of vulnerable suppliers and thus create specific control plans to mitigate supply related failures. Using this approach, organisations can devise control plans to alleviate the supplier related risks during new product development. Although, the methodology is illustrated through an application in aircraft manufacturing, it can also be used in other discrete and process manufacturing industries. 相似文献
9.
Abasi Abudulimu;Steven Carter;Adam B. Phillips;Deng-Bing Li;Sabin Neupane;Tyler Brau;Jared Friedl;Ebin Bastola;Manoj K. Jamarkattel;Michael J. Heben;Yanfa Yan;Randy J. Ellingson; 《Solar RRL》2024,8(10):2400131
Cadmium telluride (CdTe) solar cells represent a commercially successful photovoltaic technology, with an annual production capacity approaching 20 GW. However, improving the open-circuit voltage (VOC) remains challenging. This study aims to deepen the understanding of charge carrier recombination in CdTe solar cells and to explore alternative dynamical characterization methods that address the limitations found in conventionally used time-resolved photoluminescence for CdTe solar cells. Transient photovoltage and transient photocurrent techniques are utilized to investigate charge carrier dynamics under conditions resembling real-world solar cell operation. The results reveal that an effective nonradiative recombination lifetime of 580 ns dominates the charge dynamics at VOC values below 850 mV. Above this threshold, radiative recombination becomes significant, with a radiative recombination coefficient of 1.1 × 10−9 cm3 s−1. Additionally, the stationary charge carrier density at 1 sun is determined to be around 1 × 1014 cm−3. By accurately determining both radiative and nonradiative recombination, this work provides a comprehensive understanding of carrier dynamics in high-performing CdTe devices and paves the way for improving the VOC and performance of CdTe solar cells. 相似文献
10.
Sima Kashi Russell Varley Mandy De Souza Salwan Al-Assafi Adriano Di Pietro Christelle de Lavigne 《Polymer-Plastics Technology and Engineering》2018,57(16):1687-1696
An accelerated aging study on silicone rubber exploring the effects of exposure to a functional oil (polyalkylene glycol) at elevated temperature (195°C) is reported in this paper. Variations in mechanical (tensile, tear, hardness) and thermal (conductivity, specific heat capacity) properties were monitored versus aging time while permanent deformation of the rubber was evaluated through creep and recovery measurements. Morphology and surface chemistry of the aged rubber were also investigated through scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, respectively. Aging had a significant impact on the mechanical properties with the ultimate tensile strength and elongation at break decreasing from 7.4?MPa and 2250% in unaged samples to 1.5?MPa and 760% in 6-week aged samples, respectively. The tear strength and hardness exhibited an initial increase during the early stages of aging, followed by a decreasing trend. In contrast, the thermal properties did not change significantly and FTIR did not detect any changes in the surface chemistry of the rubber with aging. SEM however, provided evidence of an increase in brittle behavior from the morphology of the fractured surfaces. 相似文献