全文获取类型
收费全文 | 400篇 |
免费 | 33篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 5篇 |
综合类 | 5篇 |
化学工业 | 143篇 |
金属工艺 | 9篇 |
机械仪表 | 19篇 |
建筑科学 | 9篇 |
矿业工程 | 2篇 |
能源动力 | 12篇 |
轻工业 | 19篇 |
水利工程 | 1篇 |
石油天然气 | 2篇 |
武器工业 | 9篇 |
无线电 | 96篇 |
一般工业技术 | 66篇 |
冶金工业 | 13篇 |
原子能技术 | 3篇 |
自动化技术 | 21篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 9篇 |
2020年 | 7篇 |
2019年 | 6篇 |
2018年 | 3篇 |
2017年 | 21篇 |
2016年 | 6篇 |
2015年 | 12篇 |
2014年 | 12篇 |
2013年 | 29篇 |
2012年 | 23篇 |
2011年 | 43篇 |
2010年 | 27篇 |
2009年 | 20篇 |
2008年 | 32篇 |
2007年 | 26篇 |
2006年 | 16篇 |
2005年 | 20篇 |
2004年 | 14篇 |
2003年 | 19篇 |
2002年 | 14篇 |
2001年 | 8篇 |
2000年 | 10篇 |
1999年 | 12篇 |
1998年 | 7篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有434条查询结果,搜索用时 15 毫秒
1.
2.
Preparation and characterisation of an easily absorbabl Mg‐casein hydrolysate complex produced through enzymatic hydrolysis and ultrafiltration 下载免费PDF全文
Hye‐Jin Hong En‐jin Kim In‐Su Park Jung‐Ho Ryu Taegong Ryu Byoung‐Gyu Kim Kang‐Sup Chung 《International Journal of Food Science & Technology》2015,50(2):365-371
In this study, we synthesised a Mg‐casein hydrolysate complex that allowed the effective absorption of Mg. The type of enzyme (papain, alcalase 2.4 L, pepsin, trypsin) and the enzyme/substrate ratio for casein hydrolysis was optimised. When the enzyme/substrate ratio was 30%, the alcalase 2.4 L‐hydrolysate showed the highest Mg‐chelation efficiency, of 96.1%. To characterise and enhance the function of casein hydrolysate, we fractionated the casein hydrolysate according to molecular weight using ultrafiltration. The Mg‐chelation efficiency was increased with the decrease in the molecular‐weight range of the hydrolysate fractions. The smallest casein hydrolysate (fraction 5, 1 kDa<) is used for preparation of Mg‐casein hydrolysate complex. Synthesised Mg‐casein hydrolysate complex (fraction 5) exhibited 100% Mg solubility and 39.5% Mg bioavailability. These results indicated that the Mg‐casein hydrolysate remained a stable chelate during simulated gastro‐intestinal digestion in vitro. The Mg‐casein hydrolysate complex exhibited excellent antioxidant activity as well as Mg binding. 相似文献
3.
Jung Seop Lim Soo Hyung Ban Dong Sup Kim Kwang Yeol Kwon Sang Hoon Lee Jong Kwan Lim Sung Hwan Cho 《应用聚合物科学杂志》2020,137(37):49084
We investigated the appearance of flow and weld lines when metallic pigments are used in polymer blends and how such lines can be eliminated by improving the pigment particle shape and optimizing pigment loading. Acrylonitrile butadiene styrene copolymer and two types of aluminum flakes, lamellar and three-dimensional (3D), were blended in a twin-screw extruder with a screw diameter of 25 mm. The temperatures from the hopper to the nozzle were 140, 180, 220, 220, 220, 220, and 220°C. Weld and flow lines were observed using field-emission scanning electron microscopy and energy dispersive X-ray spectroscopy of specially manufactured injection specimens. In the flow line region, traditional lamellar flakes were randomly oriented, while 3D flakes exhibited a distinct and stable orientation. Based on these observations, flow and weld lines in a finished metal/polymer blend can be minimized by using 3D metal particles in place of lamellar flakes. We also investigated the effects of aluminum flake loading on weld and flow line visibility. At low loading, weld lines were clearly visible due to the lack of pigmentation in the front of the polymer flow. Conversely, high loading resulted in relatively high concentrations of pigment near the weld line area, reducing weld line visibility. These findings suggest that there is an optimum metal loading level where the visibility of flow and weld lines is minimized. 相似文献
4.
Effect of surface modification of anode with surfactant on the performance of microbial fuel cell 下载免费PDF全文
Young‐Chae Song Dae‐Sup Kim Jung‐Hui Woo Bakthavachallam Subha Seong‐Ho Jang Subpiramaniyam Sivakumar 《国际能源研究杂志》2015,39(6):860-868
Surface modification of anode using surfactant has great influence on the electrical performance of a microbial fuel cell (MFC). In this study, the effect of surface‐modified exfoliated graphite used for anode fabrication on a cube‐type MFC batch reactor was examined. The surface exfoliated graphite was modified with 5‐mM anionic surfactant, sodium dodecyl sulfate. Anaerobic sludge used as inoculum containing 70% (v/v) of artificial wastewater and 30% (v/v) of seed sludge in an anode chamber and air cathode was used in cathode side. Anode modification was explored as an approach to enhance the start‐up and improve the performance of the reactor. Scanning electron microscopy was used to evaluate the morphology and activity of electrochemically active bacteria. In the study, the start‐up time of MFC required to approach stable voltage was substantially reduced, and the maximum stable voltage was higher than the control. In addition, the activation resistance of the MFC was considerably reduced, and the maximum power density (1640 mW/m2) was 20% higher than control. However, when the surface of exfoliated graphite was modified with over 10‐mM anionic surfactant, some negative effects on start‐up time, activation resistance and maximum power density were observed. This modification also enhanced the bacterial attachment and biofilm formation on the modified anode surface. The result suggested that surface modification anode with surfactant is effective for electrical responses achieved in the MFC. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
5.
Cheol Park Won Sup Lee Se-Il Go Arulkumar Nagappan Min Ho Han Su Hyun Hong Gon Sup Kim Gi Young Kim Taeg Kyu Kwon Chung Ho Ryu Sung Chul Shin Yung Hyun Choi 《International journal of molecular sciences》2015,16(1):645-659
Evidence suggests that phytochemicals can safely modulate cancer cell biology and induce apoptosis. Here, we investigated the anti-cancer activity of morin, a flavone originally isolated from members of the Moraceae family in human leukemic cells, focusing on apoptosis. An anti-cancer effect of morin was screened with several human leukemic cell lines. U937 cells were most sensitive to morin, where it induced caspase-dependent apoptosis in a dose-dependent manner. It also induced loss of MMP (ΔΨm) along with cytochrome c release, down-regulated Bcl-2 protein, and up-regulated BAX proteins. The apoptotic activity of morin was significantly attenuated by Bcl-2 augmentation. In conclusion, morin induced caspase-dependent apoptosis through an intrinsic pathway by upregulating BAD proteins. In addition, Bcl-2 protein expression is also important in morin-induced apoptosis of U937 cells. This study provides evidence that morin might have anticancer properties in human leukemic cells. 相似文献
6.
7.
Won So Young-Hun Kim Chang Jun Lee Dongil Shin En Sup Yoon 《Korean Journal of Chemical Engineering》2011,28(3):656-666
Accidents involving domino effects are more serious than other type of accidents. Although there have been studies on such
accidents, it is still difficult to examine the actual factors and causes since the domino effect is influenced nonlinearly
by factors involving flame, overpressure, and flying objects. We considered the case of adding new facilities to an existing
system in a given site. The layout of new facilities suggests positions that minimize the domino effects, based on nonlinear
optimization taking domino factors into account. We quantitatively calculated the domino risk of each facility through the
concept of combined domino factors (flame, overpressure, and missile). Also, we identified variations of domino damage extent
of the target system through comparison of the impacts of domino effect when additional facilities were installed. Simulated
annealing was adopted for searching optimal positions. As a case study, we applied the proposed method to the case of adding
DME storage tanks in the existing LPG charging facilities. The presented framework of the quantitative assessment of domino
risk and safety standard for the layout of additional facilities would be useful for proper layout design for improved accident
prevention. 相似文献
8.
The negative pore-water pressure in unsaturated soils increases the inter-particle force and small-strain stiffness, though this concept is only valid in wettable soils. The non-wetting nature of soils originating from the organic contamination of geoenvironments and natural hazards causes unexpected geo-events such as impermeation of water and hillslope runoff due to the changes in soil wettability. This study presents an experimental and numerical investigation to understand the evolution of capillary force and pressure for unsaturated soils whose surface wettability is wettable (hydrophilic) and water-repellent (hydrophobic). Hydrophobic granular materials are synthesized by the silanization technique with 0.5 mm diameter glass beads. The small-strain shear stiffness and corresponding degree of saturation are continuously monitored during evaporation for both specimens. The peak value of maximum shear stiffness is captured at a degree of saturation S~5.5% for hydrophilic specimen, while the hydrophobic specimen shows a quasi-constant small-strain stiffness during evaporation. The minimization of free energy for the liquid bridge between the two-particle system allows the attractive and repulsive capillary force and pressure produced between particles to be numerically estimated. The regime of zero-capillary pressure is identified depending on the contact angle and volume of liquid bridge. The measurement of small-strain stiffness combined with the numerical simulation of both hydrophilic and hydrophobic specimens clarifies the governing factors to determine capillarity in the granular materials and provides insight into the phenomenological observation of capillary pressure for unsaturated soils. 相似文献
9.
Kyungtae Park Jamin Koo Dongil Shin Chang Jun Lee En Sup Yoon 《Korean Journal of Chemical Engineering》2011,28(4):1009-1018
A general mathematical programming formulation which also considers safety factors is presented for solving the multi-floor
plant layout problem. In the presence of a risk of physical explosion, the safety distance must be considered to generate
more reasonable and safe layouts. The proposed method determines detailed multi-floor process plant layouts using mixed integer
linear programming (MILP). To consider the safety distance, a consequence analysis is adopted for calculating an equipment
physical explosion probit. As the TNT equivalency method is used, more realistic estimations of equipment damage are possible,
generating safer plant layouts. The objective function minimizes the layout cost (total plant area, floor construction costs
and connection costs) and explosion damage costs for the multi-floor problem. Two illustrative examples are presented to demonstrate
the applicability of the proposed method. 相似文献
10.
Optical Waveguiding: Remote Biosensing with Polychromatic Optical Waveguide Using Blue Light‐Emitting Organic Nanowires Hybridized with Quantum Dots (Adv. Funct. Mater. 24/2014) 下载免费PDF全文