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51.
Sexual coercion, a topic of relevance to school health personnel, may be as common in high school populations as in university populations. Twenty-one sexuality education curricula were examined for information on the topics of date rape, stranger rape, pressure, incest, sexual harassment, unwanted/inappropriate touch, and exploitation/victimization. Curricula scoring highest in total coverage also were the most comprehensive with six of the seven sexual coercion topics covered. Overall, pressure and exploitation/victimization received the greatest attention, while sexual harassment was not covered in any of the curricula. Common themes occurring within the coercion topic areas included guilt, communication/assertiveness skills, blame, drug use, premeditation, fear, sources of help. Results suggest sexuality education curricula have not responded to the increased concern regarding sexual harassment in schools. 相似文献
52.
Because changes in intracellular Ca2+ affect progression through the mitotic cell cycle, we investigated the role of Ca2+-binding proteins in regulating cell cycle progression. Evidence was found demonstrating that the activation of Ca2+/calmodulin-dependent protein kinase (CaM kinase) inhibits cell cycle progression in small cell lung carcinoma (SCLC) cells. We also demonstrated that SCLC cells express both CaM kinase type II (CaMKII) and CaM kinase type IV (CaMKIV). Five independent SCLC cell lines expressed proteins reactive with antibody to the CaMKII beta subunit, but none expressed detectable proteins reactive with antibody to the CaMKII alpha subunit. All SCLC cell lines tested expressed both the alpha and beta isoforms of CaMKIV. Immunoprecipitation of CaMKII from SCLC cells yielded multiple proteins that autophosphorylated in the presence of Ca2+ / calmodulin. Autophosphorylation was inhibited by the CaMKII(281-302) peptide, which corresponds to the CaMKII autoinhibitory domain, and by 1-[N,O-bis(5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4- phenylpiperazine (KN-62), a specific CaM kinase antagonist. Influx of Ca2+ through voltage-gated Ca2+ channels stimulated phosphorylation of CaMKII in SCLC cells, and this was inhibited by KN-62. Incubation of SCLC cells of KN-62 potently inhibited DNA synthesis, and slowed progression through S phase. Similar anti-proliferative effects of KN-62 occurred in SK-N-SH human neuroblastoma cells, which express both CaMKII and CaMKIV, and in K562 human chronic myelogenous leukemia cells, which express CaMKII but not CaMKIV. The expression of both CaMKII and CaMKIV by SCLC cells, and the sensitivity of these cells to the anti-proliferative effects of KN-62, suggest a role for CaM kinase in regulating SCLC proliferation. 相似文献
53.
Winn Schwartau 《Network Security》1997,1997(9):17-19
This series of articles, based on the author's book Information Warfare, investigates the issues concerning businesses wishing to protect themselves from the very real possibility of information warfare. We consider what the problems are and how they can be combatted over the course of the next few issues of the newsletter. This particular article outlines the details of Class 1 Information Warfare. 相似文献
54.
Yin P Criminisi A Winn J Essa I 《IEEE transactions on pattern analysis and machine intelligence》2011,33(1):30-42
This paper presents an automatic segmentation algorithm for video frames captured by a (monocular) webcam that closely approximates depth segmentation from a stereo camera. The frames are segmented into foreground and background layers that comprise a subject (participant) and other objects and individuals. The algorithm produces correct segmentations even in the presence of large background motion with a nearly stationary foreground. This research makes three key contributions: First, we introduce a novel motion representation, referred to as "motons," inspired by research in object recognition. Second, we propose estimating the segmentation likelihood from the spatial context of motion. The estimation is efficiently learned by random forests. Third, we introduce a general taxonomy of tree-based classifiers that facilitates both theoretical and experimental comparisons of several known classification algorithms and generates new ones. In our bilayer segmentation algorithm, diverse visual cues such as motion, motion context, color, contrast, and spatial priors are fused by means of a conditional random field (CRF) model. Segmentation is then achieved by binary min-cut. Experiments on many sequences of our videochat application demonstrate that our algorithm, which requires no initialization, is effective in a variety of scenes, and the segmentation results are comparable to those obtained by stereo systems. 相似文献
55.
The corrosion behavior of Co-Cr and Ni-Fe alloys is reported after exposure to Cl2 , SO2 , and O2 containing test atmospheres at various relative (RH) humidities. Surface Chemistry, physical features, and magnetic properties were characterized. The Ni-Fe alloys exhibited excellent corrosion resistance in elevated RH atmospheres. Co-Cr alloys showed little change in magnetic properties even when significant chemical penetration of the film occurred. Substrate chemical composition proved to be an important factor in sputtered film corrosion behavior. 相似文献
56.
The literature on the spread and vaporisation of cryogenic liquids on water is reviewed and a new model proposed. The model incorporates the features o
T001. List of symbols
Symbols | |
Cp | Heat capacity. |
g | Acceleration due to gravity. |
Gm | Molar vaporisation rate. |
h | Latent heat with two suffices denoting phase change. |
h | Pool thickness (no suffices). |
i | Enthalpy. |
k,K | Constants. |
KA,KB | Functions of pool temperature and composition. |
kw | Thermal diffusivity of water. |
l | Depth in water where temperature is constant. |
L | Length scale of an oil spill. |
Lm | Molar liquid spill rate. |
Lwi | Latent heat of fusion of ice. |
M | Pool mass, M0 initially. |
Ms,Mv | Mass spilled, mass vaporised. |
q | Heat flux to cryogenic liquid. |
r | Radial co-ordinate |
R,R* | Radius of pool. |
t | Time. |
T | Temperature. |
U | Velocity. |
Wm | Number of moles of material in the pool. |
xA | Molar methane portion of liquid pool (xB, ethane). |
xAS | Molar methane portion of spilling liquid. |
yA | Molar methane portion of vapour (yB, ethane). |
z | Vertical coordinate. |
δ | Vapour layer thickness. |
ΔT | Temperature difference. |
? | Ice layer thickness. |
θ | Temperature relative to freezing point of water. |
λ | Effective thermal conductivity. |
μ | Viscosity. |
? | Density. |
σ | Surface tension. |
ø | Heat flux to liquid pool = q. |
Suffices | |
A | Average (or methane fraction with x,y). |
B | Boiling point of cryogen (or ethane fraction with x,y). |
fc | Film collapse. |
fg | Liquid to vapour phase change. |
F | Freezing of water. |
i | Ice. |
l, L | Liquid. |
lv | Liquid to vapour phase change. |
LE | Leading edge. |
m | Molar. |
O | Initial |
o | Oil. |
p | Pool. |
s | Spilling liquid. |
v | Vapour. |
w | Water. |