全文获取类型
收费全文 | 116篇 |
免费 | 9篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 24篇 |
金属工艺 | 5篇 |
机械仪表 | 2篇 |
建筑科学 | 1篇 |
能源动力 | 6篇 |
轻工业 | 12篇 |
水利工程 | 1篇 |
无线电 | 23篇 |
一般工业技术 | 20篇 |
冶金工业 | 11篇 |
自动化技术 | 19篇 |
出版年
2023年 | 2篇 |
2022年 | 8篇 |
2021年 | 10篇 |
2020年 | 7篇 |
2019年 | 7篇 |
2018年 | 9篇 |
2017年 | 10篇 |
2016年 | 3篇 |
2015年 | 5篇 |
2014年 | 7篇 |
2013年 | 7篇 |
2012年 | 4篇 |
2011年 | 8篇 |
2009年 | 2篇 |
2008年 | 6篇 |
2007年 | 6篇 |
2006年 | 6篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 2篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 4篇 |
1995年 | 1篇 |
1993年 | 2篇 |
1991年 | 1篇 |
1986年 | 1篇 |
排序方式: 共有125条查询结果,搜索用时 15 毫秒
81.
Ritesh K. Baboota Mahendra Bishnoi Padma Ambalam Kanthi Kiran Kondepudi Siddhartha M. Sarma Ravneet K. Boparai Koteswaraiah Podili 《Journal of Functional Foods》2013,5(3):997-1012
Worldwide obesity has reached a pandemic proportion. World Health Organization (WHO) estimates that by 2020, two thirds of the global disease burden will be attributable to obesity and obesity associated complications. Existing anti-obesity drugs, affecting one of the fundamental processes of the weight regulation in human body, have displayed serious side effects which outweigh their beneficial effects. Clinical and non-clinical researchers in this area are now facing a challenge to search for non-pharmacological alternatives for the prevention of obesity. Dietary interventions and life style changes with enhanced physical activity are two such options. Considering the importance of dietary interventions, the present review highlights the role, significance and potential of functional food ingredients for the management of obesity and associated co-morbidities. 相似文献
82.
Ritesh Gupta 《Microelectronics Journal》2006,37(9):919-929
In the proposed work the model has been formulated for discretized doped HEMT, where the conventional uniformly doped, pulsed doped and delta doped structure are the special cases. An expression for sheet carrier density has been formulated considering the effect of doping-thickness product and has been extended to calculate drain current, transconductance, capacitance and cut-off frequency of the device. The model also takes into account the non-linear relationship between sheet carrier density and quasi Fermi energy level to validate it from subthreshold region to high conduction region. The results so obtained have been compared with pulsed doped structure to validate the model. The analysis concentrates on the distance of doping from the heterojunction and gate electrode. Different design criteria have been given to dope the carriers (amount and distance) in different regions to optimize the performance for higher sheet carrier density/parallel conduction voltage/effective parallel conduction voltage (Vc−Voff) to increase the transconductance, cut-off frequency and reliability of the device. 相似文献
83.
84.
Ritesh Rawal Antonio Feteira Neil C. Hyatt Derek C. Sinclair Kumaravinothan Sarma Neil McN. Alford 《Journal of the American Ceramic Society》2006,89(1):332-335
The dielectric properties of dense ceramics of the n =0 member of a newly identified homologous series Ba3+ n LaNb3 Ti n O12+3 n , where n =0, 1, and 2, are reported. Single-phase powders can be obtained from the mixed-oxide route at 1350°C and dense ceramics (>97% of the theoretical X-ray density) with uniform microstructures (3–5 μm) can be obtained by sintering in air at 1500°C. The ceramics are excellent dc insulators with a band gap >2.6 eV that resonate at microwave frequencies with a relative permittivity, ɛr ∼44, a quality factor, Q × f r , of ∼9000 at f r ∼5.5 GHz and a temperature coefficient of resonant frequency, TCf ,∼−100 ppm/K. 相似文献
85.
I Mahmud N Ueda H Yamaguchi R Yamashita S Yamamoto Y Kanaoka Y Urade O Hayaishi 《Canadian Metallurgical Quarterly》1997,272(45):28263-28266
The cytosol fraction of human platelets did not convert prostaglandin (PG) H2 to PGD2. However, a homogenate of human megakaryoblastic CMK cells (precursor cells of platelets) produced PGD2 from PGH2. The PGD synthase activity was localized in the cytosol of CMK cells, and absolutely required glutathione. The catalytic properties and Western and Northern blottings indicated that the enzyme was PGD synthase of the hematopoietic type rather than the lipocalin type. When CMK cells were differentiated to megakaryocytes with phorbol ester along with induction of cyclooxygenase-1, the PGD synthase activity increased about 2-fold for 2 days and then decreased. In another human megakaryoblastic cell line, Dami, the PGD synthase increased about 10-fold by the addition of phorbol ester. Thus, the PGD synthase, which was undetectable in platelets, appeared during differentiation of megakaryoblasts to megakaryocytes. 相似文献
86.
RiteshMastipuram 《电子设计应用》2004,(2):123-124,127
软误差是半导体器件中无法有意再生的“干扰”(即数据丢失)。它是由那些不受设计师控制的外部因素所引起的,包括α粒子、宇宙射线和热中子。许多系统能够容忍一定程度的软误差。例如,如果为音频、视频或静止成像系统设计一个预压缩捕获缓冲器或后置解压缩重放缓冲器,则一个偶然出现的缺陷 相似文献
87.
Integrating nanophotonics with electronics could enhance and/or enable opportunities in areas ranging from communications and computing to novel diagnostics. Light sources and detectors are important elements for integration, and key progress has been made using semiconducting nanowires and carbon nanotubes to yield electrically driven sources and photoconductor detectors. Detection with photoconductors has relatively poor sensitivity at the nanometre scale, and thus large amplification is required to detect low light levels and ultimately single photons with reasonable response time. Here, we report avalanche multiplication of the photocurrent in nanoscale p-n diodes consisting of crossed silicon-cadmium sulphide nanowires. Electrical transport and optical measurements demonstrate that the nanowire avalanche photodiodes (nanoAPDs) have ultrahigh sensitivity with detection limits of less than 100 photons, and subwavelength spatial resolution of at least 250 nm. Crossed nanowire arrays also show that nanoAPDs are reproducible and can be addressed independently without cross-talk. NanoAPDs and arrays could open new opportunities for ultradense integrated systems, sensing and imaging applications. 相似文献
88.
Gurdeep Singh S. K. Gupta Ritesh Kumar M. Sunderarajan 《Canadian Metallurgical Quarterly》2007,133(12):1088-1097
Ground and surface water contamination due to leaching of trace elements from ash ponds is a major environmental challenge for thermal power plants. Leaching of trace elements from the ash ponds indicated significant concentration of nine trace elements (Na, K, Mg, Ca, Fe, Pb, Mn, Cu, and Zn) in the leachates of various thermal power plants. The empirical models developed for the prediction of various trace elements i.e., Mn, Cu, Fe, Zn, and Pb, followed first-order reaction rate kinetics. The empirical models derived from the laboratory scale models were subsequently modified to account for the changes in the chemistry, mineralogy, and morphology of fly ash with respect to time which correlated well with the real field data with regression coefficients varying from 0.93 to 0.98. The modified empirical models predicted concentrations of the trace elements within ±3% of the observed values for four thermal power plants with standard deviation varying from 0.001 to 0.032. 相似文献
89.
The mechanism of lasing in single cadmium sulfide (CdS) nanowire cavities was elucidated by temperature-dependent and time-resolved photoluminescence (PL) measurements. Temperature-dependent PL studies reveal rich spectral features and show that an exciton-exciton interaction is critical to lasing up to 75 K, while an exciton-phonon process dominates at higher temperatures. These measurements together with temperature and intensity dependent lifetime and threshold studies show that lasing is due to formation of excitons and, moreover, have implications for the design of efficient, low threshold nanowire lasers. 相似文献
90.
Ritesh Haldar Lars Heinke Christof Wöll 《Advanced materials (Deerfield Beach, Fla.)》2020,32(20):1905227
When fabricating macroscopic devices exploiting the properties of organic chromophores, the corresponding molecules need to be condensed into a solid material. Since optical absorption properties are often strongly affected by interchromophore interactions, solids with a well-defined structure carry substantial advantages over amorphous materials. Here, the metal–organic framework (MOF)-based approach is presented. By appropriate functionalization, most organic chromophores can be converted to function as linkers, which can coordinate to metal or metal-oxo centers so as to yield stable, crystalline frameworks. Photoexcitations in such chromophore-based MOFs are surveyed, with a special emphasis on light-switchable MOFs from photochromic molecules. The conventional powder form of MOFs obtained using solvothermal approaches carries certain disadvantages for optical applications, such as limited efficiency resulting from absorption and light scattering caused by the (micrometer-sized) powder particles. How these problems can be avoided by using MOF thin films is demonstrated. 相似文献