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21.
The seed oil ofCelastrus orbiculatus (family Celastraceae) was reinvestigated to determine whether the benzoic acid that it contains is esterified with glycerol. Unlike acetic acid, benzoic acid is not incorporated in glycerides of this oil but, instead, is esterified with two sesquiterpenoid triols of the empirical formula C15H26O4.trans-Cinnamic acid also is esterified with these triols. Acetic acid is a component of these nonglyceride esters, as well as of the triglycerides. We found no evidence for the occurrence of formic acid in this oil. By countercurrent fractionation, we found that this oil contains 8% “ordinary” triglycerides, 59% mono-acetotriglycerides, and 33% nonglyceride substances. 相似文献
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23.
SG Ellis AM Lincoff D Miller JE Tcheng NS Kleiman D Kereiakes R Califf EJ Topol 《Canadian Metallurgical Quarterly》1998,32(6):1619-1623
OBJECTIVES: We investigated the hypothesis that abciximab might lead to a differential effect among patients with different lesion morphologies; hence, its cost/benefit ratio would be optimized if it were used selectively on the basis of baseline angiographic findings. BACKGROUND: Major complications of coronary angioplasty occur in 4% to 9% of patients. In the Evaluation of 7E3 for the Prevention of Ischemic Complications (EPIC) and Evaluation of PTCA To Improve Long-term Outcome with abciximab GPIIb/IIIa Receptor Blockade (EPILOG) trials, abciximab decreased the ischemic complications after intervention by 35% to 56%. However, the cost of this agent is appreciable, and there remain concerns about the safety of its readministration. METHODS: There were 1,362 patients in EPIC and 2,792 patients in EPILOG randomized to either bolus plus an infusion of abciximab or placebo, administered with aspirin and heparin at the time of the coronary intervention. Data from these studies were combined, and a differential effect of abciximab in relation to baseline lesion morphology on 30-day risk of death, myocardial infarction or urgent intervention was investigated using the Breslow Day test for statistical interaction. RESULTS: Abciximab consistently reduced the relative risk of complications across all lesion morphologies studied, with the possible exception of patients treated with degenerated saphenous vein grafts (risk with placebo 16.3% vs. risk with abciximab 18.6%, Breslow Day test for interaction, p=0.08). However, the absolute reduction of risk was somewhat greater in patients with more complex B2 or C lesions (7.6% and 5.8%, respectively) than in patients with morphologically simpler A or B1 lesions (3.7% and 3.2%, respectively). CONCLUSIONS: The reduction of early adverse ischemic events associated with angioplasty by abciximab occurs largely independent of pretreatment morphology. 相似文献
24.
The apparent discrepancy that an element with the richest chemistry of all should possess only few polymorphs was resolved recently by the increasing recognition of carbynes, chain-like compounds with sp-configuration and conjugated triple or cumulated double bonds between the carbon atoms in the chain. A simple classification approach is suggested leading to a linear relationship between the number of atoms in the chain and the c-axes lengths, the cell volumes, and the ratio. Moreover, a new carbyne form was observed which may have originated from regraphitization of shock-formed diamond. The new carbon polymorph fits well in the gap between already known carbyne forms. 相似文献
25.
HA Dakik NS Kleiman JA Farmer ZX He JA Wendt CM Pratt MS Verani JJ Mahmarian 《Canadian Metallurgical Quarterly》1998,98(19):2017-2023
BACKGROUND: Patients who have inducible ischemia after acute myocardial infarction (AMI) generally undergo coronary angiography with the intent to revascularize. Whether this approach is superior to intensive treatment with anti-ischemic medications is unknown. METHODS AND RESULTS: We performed a prospective, randomized pilot study comparing intensive medical therapy with coronary angioplasty (PTCA) for suppression of myocardial ischemia in 44 stable survivors of AMI. Myocardial ischemia was quantified with adenosine 201Tl tomography (SPECT) performed 4.5+/-2.9 days after AMI. All patients at baseline had a large total (>/=20%) and ischemic (>/=10%) left ventricular perfusion defect size (PDS). SPECT was repeated at 43+/-26 days after therapy was optimized. The total stress-induced PDS was comparably reduced with medical therapy (from 38+/-13% to 26+/-16%; P<0.0001) and PTCA (from 35+/-12% to 20+/-16%; P<0.0001). The reduction in ischemic PDS was also similar (P=NS) in both groups. Cardiac events occurred in 7 of 44 patients over 12+/-5 months. Patients who remained clinically stable had a greater reduction in ischemic PDS (-13+/-9%) than those who had a recurrent cardiac event (-5+/-7%; P<0.02). Event-free survival was superior in the 24 patients who had a significant (>/=9%) reduction in PDS (96%) compared with those who did not (65%; P=0.009). CONCLUSIONS: In this small pilot study, intensive medical therapy and PTCA were comparable at suppressing ischemia in stable patients after AMI. Sequential imaging with adenosine SPECT can track changes in PDS after anti-ischemic therapies and thereby predict subsequent outcome. Corroboration of these preliminary findings in a larger cardiac-event trial is warranted. 相似文献
26.
Seed oils of the order Umbelliflorae, including those from the families Umbelliferae, Garryaceae, Araliaceae, Cornaceae, Davidiaceae,
Nyssaceae and Alangiaceae, were analyzed for fatty acid composition by gas liquid chromatography (GLC) of their methyl esters.
The characteristic fatty acid of the order, petroselinic acid, occurred in the Umbelliferae in amounts up to 85%. In the Araliaceae,
the content was as high as 83% and in the Garryaceae as high as 81%. The other major acids were palmitic, oleic and linoleic
acids, with small amounts of hexadecenoic, stearic, linolenic, and, in some cases, C20 acids. petroselinic acid was determined by microscale ozonolysis of the C18 monoenoic esters and subsequent GLC of the ozonolysis products. The occurrence of high oil contents (up to 46%) combined
with exceptionally high (up to 83%) single component purity is notable and emphasizes the potential of the Umbelliflorae as
a raw material source for the chemical industry. 相似文献
27.
28.
We present a robust method to find region‐level correspondences between shapes, which are invariant to changes in geometry and applicable across multiple shape representations. We generate simplified shape graphs by jointly decomposing the shapes, and devise an adapted graph‐matching technique, from which we infer correspondences between shape regions. The simplified shape graphs are designed to primarily capture the overall structure of the shapes, without reflecting precise information about the geometry of each region, which enables us to find correspondences between shapes that might have significant geometric differences. Moreover, due to the special care we take to ensure the robustness of each part of our pipeline, our method can find correspondences between shapes with different representations, such as triangular meshes and point clouds. We demonstrate that the region‐wise matching that we obtain can be used to find correspondences between feature points, reveal the intrinsic self‐similarities of each shape and even construct point‐to‐point maps across shapes. Our method is both time and space efficient, leading to a pipeline that is significantly faster than comparable approaches. We demonstrate the performance of our approach through an extensive quantitative and qualitative evaluation on several benchmarks where we achieve comparable or superior performance to existing methods. 相似文献
29.
Either 9-hydroperoxy-trans-10,cis-12-octadecadienoic acid or 13-hydroperoxy-cis-9,trans-11-octadecadienoic acid was treated with the catalyst, cysteine-FeCl3, in the presence of oxygen. Oxohydroxyoctadecenoic acids were among the many products formed as a result of hydroperoxide
decomposition. A mixture of 9(13)-oxo-13(9)-hydroxy-trans-11(10)-octadecenoic acids (δ-ketols) was produced from either isomeric hydroperoxide. The formation of isomeric δ-ketols
from 9-hydroxy-trans-12,13-epoxy-trans-10-octadecenoic acid (epoxyol), a known product of 13-hydroperoxy-cis-9,trans-11-octadecadienoic acid decomposition, implies that the epoxyol is an intermediate. The mechanism was elucidated by the facile
conversion of the epoxyol (methyl ester_ to methyl 9(13)-oxo-13(9)-hydroxy-trans-11(10)-octadecenoates with a Lewis acid, BF3-etherate.
Presented at the 14th World Congress, International Society for Fat Research, Brighton, U.K., September 17–22, 1978.
The mention of firm names or trade products does not imply that they are endorsed or recomended by the U.S. Department of
Agriculture over other firms or similar products not mentioned. 相似文献
30.
Mono- and polyestolides, made from oleic acid, meadowfoam oil fatty acids and erucic acid, were subjected to biodegradation
with mixed cultures of Penicillium verucosum, Mucor racemosus, and Enterobacter aerogenes. Fermentations were continued for 3, 5, 10, 15, 20, or 30 d. Meadowfoam oil and its fatty acids, oleic acid and soybean oil
were also biodegraded under the same conditions. After 10 d, oleic acid and soybean oil were degraded 99.8 and 99.2%, respectively;
meadowfoam oil and its fatty acids were degraded 89.0 and 97.7%, respectively. After 30 d, oleic acid-derived poly- and monoestolides
were degraded 98.6 and 90.0%, respectively, meadowfoam estolides were degraded 75.7%, and erucic acid estolides were degraded
84.0%. 相似文献