全文获取类型
收费全文 | 395篇 |
免费 | 8篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 45篇 |
金属工艺 | 5篇 |
机械仪表 | 12篇 |
建筑科学 | 17篇 |
能源动力 | 16篇 |
轻工业 | 50篇 |
水利工程 | 1篇 |
石油天然气 | 4篇 |
无线电 | 23篇 |
一般工业技术 | 45篇 |
冶金工业 | 109篇 |
原子能技术 | 4篇 |
自动化技术 | 71篇 |
出版年
2021年 | 8篇 |
2020年 | 3篇 |
2019年 | 11篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 8篇 |
2015年 | 5篇 |
2014年 | 9篇 |
2013年 | 20篇 |
2012年 | 19篇 |
2011年 | 18篇 |
2010年 | 12篇 |
2009年 | 14篇 |
2008年 | 15篇 |
2007年 | 19篇 |
2006年 | 13篇 |
2005年 | 8篇 |
2004年 | 14篇 |
2003年 | 6篇 |
2002年 | 3篇 |
2001年 | 6篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1998年 | 19篇 |
1997年 | 8篇 |
1996年 | 12篇 |
1995年 | 12篇 |
1994年 | 15篇 |
1993年 | 10篇 |
1992年 | 5篇 |
1991年 | 8篇 |
1990年 | 5篇 |
1989年 | 10篇 |
1988年 | 7篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 9篇 |
1984年 | 8篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 6篇 |
1979年 | 4篇 |
1977年 | 7篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1974年 | 4篇 |
1971年 | 2篇 |
1944年 | 1篇 |
1926年 | 1篇 |
排序方式: 共有404条查询结果,搜索用时 15 毫秒
11.
Patchimaporn Udomkun Rony Swennen Cargele Masso Bhundit Innawong Apollin Fotso Kuate Amos Alakonya Bernard Vanlauwe 《International Journal of Food Science & Technology》2021,56(10):5417-5431
The present study investigated the effect of ripening stages and chemical precursors on acrylamide formation in deep-fried chips of five plantains and one cooking banana. The highest level of acrylamide was found in the cooking banana, followed by False Horn plantain and French plantain, respectively. French plantain hybrids exhibited a significantly lower (P < 0.05) level of acrylamide when compared to French plantain. The ripening stage demonstrated a positive Pearson correlation (P < 0.05, r = 0.57) with acrylamide formation. As ripening progressed, the levels of glucose and fructose significantly increased (P < 0.05) and showed a positive correlation with acrylamide formation (r = 0.85 and 0.96, respectively). The level of the amino acid asparagine during ripening was not correlated with acrylamide formation. In contrast, the level of histidine, arginine, iso-leucine and cystine during ripening was positively correlated (P < 0.05, r > 0.60) with acrylamide formation in fried chips. The higher level of TP was significantly related (P < 0.05) to the lower level of acrylamide (r = −0.62). The reduced levels of carotenoid isomers, except lutein, during fruit ripening were positively correlated (P < 0.05) with acrylamide formation, especially trans-BC (r = 0.72) and 9-cis-BC(r = 0.64). 相似文献
12.
13.
Josiah Ochieng Olga Y. Korolkova Guoliang Li Renjie Jin Zhenbang Chen Robert J. Matusik Samuel Adunyah Amos M. Sakwe Olugbemiga Ogunkua 《International journal of molecular sciences》2022,23(7)
The present studies were conducted to evaluate key serum proteins and other components that mediate anchorage-independent growth (3-D growth) of LNCaP prostate cancer cells as spheroids. The cells were cultured on ultra-low attachment plates in the absence and presence of fetuin-A and with or without extracellular vesicles. The data show that fetuin-A (alpha 2HS glycoprotein) is the serum protein that mediates 3-D growth in these cells. It does so by sequestering extracellular vesicles of various sizes on the surfaces of rounded cells that grow as spheroids. These vesicles in turn transmit growth signals such as the activation of AKT and MAP kinases in a pattern that differs from the activation of these key growth signaling pathways in adherent and spread cells growing in 2-D. In the process of orchestrating the movement and disposition of extracellular vesicles on these cells, fetuin-A is readily internalized in adhered and spread cells but remains on the surfaces of non-adherent cells. Taken together, our studies suggest the presence of distinct signaling domains or scaffolding platforms on the surfaces of prostate tumor cells growing in 3-D compared to 2-D. 相似文献
14.
15.
Brain‐Penetrant Triazolopyrimidine and Phenylpyrimidine Microtubule Stabilizers as Potential Leads to Treat Human African Trypanosomiasis 下载免费PDF全文
Dr. Ludovica Monti Steven C Wang Dr. Killian Oukoloff Dr. Amos B. Smith III Dr. Kurt R. Brunden Dr. Conor R. Caffrey Dr. Carlo Ballatore 《ChemMedChem》2018,13(17):1751-1754
In vitro whole‐organism screens of Trypanosoma brucei with representative examples of brain‐penetrant microtubule (MT)‐stabilizing agents identified lethal triazolopyrimidines and phenylpyrimidines with sub‐micromolar potency. In mammalian cells, these antiproliferative compounds disrupt MT integrity and decrease total tubulin levels. Their parasiticidal potency, combined with their generally favorable pharmacokinetic properties, which include oral bioavailability and brain penetration, suggest that these compounds are potential leads against human African trypanosomiasis. 相似文献
16.
III Amos B. Smith Richard A. Hartz P. Grant Spoors Jon D. Rainier 《Israel journal of chemistry》1997,37(1):69-80
An efficient third-generation asymmetric synthesis of tricyclic lactone (+)-1, designed to serve as the common intermediate for construction of the indole tremorgens, has been developed. The major challenge was stereocontrolled introduction of the vicinal quaternary methyl groups. Our initial approaches employed enolate chemistry to install the second methyl moiety; herein we exploit instead a hydroxyl-directed Simmons-Smith cyclopropanation followed by reductive opening of the three-membered ring. The new 15-step synthesis proceeds in 8.3% overall yield, nearly an eightfold increase over the second-generation route, and is amenable to large-scale production of (+)- 1. 相似文献
17.
Umpolung-based strategies play a significant role in organic synthesis. Particularly important are 1,3-dithiane linchpins, which serve as convenient acyl anion equivalents. The general synthetic accessibility and impressive reactivity of 1,3-dithianes have thus led to widespread application. Since the late 1970s, dithianes have featured prominently in our program directed toward the synthesis of complex natural and unnatural products, both for effective union of advanced fragments and for multicomponent linchpin couplings. In this Account, we present the evolution of dithiane chemistry in our laboratory. 相似文献
18.
19.
Filippo de Monte James V. Beck Donald E. Amos 《International Journal of Heat and Mass Transfer》2011,54(13-14):2789-2800
A numerical approximation of the Green’s function equation based on a heat-flux formulation is given. It is derived by assuming as a functional form of the surface heat flux a stepwise variation with space and time. The obtained approximation is very important in investigation of the inverse heat conduction problems (IHCPs) because it gives a convenient expression for the temperature in terms of the heat flux components. Additionally, it is very important for the unsteady surface element (USE) method which is a modern boundary discretization method. Green’s function approximate solution equation (GFASE) also creates ‘naturally’ fixed groups or modules of work elements called “building blocks” that may be added together to obtain space and time values of temperature. In the current case, they are subject to a partial heating by an applied surface heat flux. The “building block” solution can be derived by using the various analytical and numerical approaches available in heat conduction literature though the exact analysis is preferable, as discussed in the text. Poorly-convergent series deriving from Green’s functions approach are replaced by closed-form algebraic solutions. 相似文献
20.
ABSTRACT This paper proposes an explanation of unbalanced regional growth and regional inequalities based on the view that human behaviour is motivated either to reduce the physiological state of arousal or to increase it. While arousal reduction is the basis of conventional economic analysis arousal augmentation is seldom considered. This paper argues that arousal augmentation motivates society to seek technological and socioeconomic innovations that trigger economic progress. The mechanism for this progress is seen as a synthesis of spatial growth poles and temporal long waves. 相似文献