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1.
Molecular cloning of a canine metallothionein cDNA 总被引:1,自引:0,他引:1
A canine metallothionein cDNA obtained from the liver of a cadmium-treated beagle was cloned and sequenced. Asn at position 4 conserved among all mammalian metallothionein-1 and metallothionein-2 is replaced by Asp in the canine metallothionein cDNA clone. Because the acidic amino acid doesn't exist at either position 10 or 11 in the deduced amino acid sequence, it is supposed that this cDNA is derived from canine metallothionein-1 mRNA. Northern blot analysis using the cDNA as a probe revealed the induction of the canine metallothionein mRNA expression in the liver and kidney of a cadmium-treated beagle. Thus, the canine metallothionein cDNA obtained in the present study should provide an useful tool for the molecular investigation of metallothionein in dog. 相似文献
2.
A Yoshimura Y Yamano A Gemma K Yoshimori K Hayashihara Y Taniguchi K Uematsu M Shibuya S Kudoh H Niitani 《Canadian Metallurgical Quarterly》1993,20(4):503-508
We conducted an early phase II trial in advanced non-small cell lung cancer (NSCLC) to evaluate response efficacy of a combination of Cisplatin (CDDP) and Carboplatin (CBDCA). The twenty-six patients in the study had had no previous treatment. They received a sequential administration of 300 mg/m2 CBDCA and 80 mg/m2 CDDP with approximately 3,500 ml of hydration on day 1 every 4 weeks. All patients were evaluable for response and toxicity. Ten (38.5%) of all assessable patients achieved a partial response (95% confidence interval, 19.8-57.2%). Response rates for patients with stage III A, III B and IV- disease were 40.0 (2/5), 70.0 (7/10) and 9.1% (1/11), respectively. Response rates for patients with squamous cell carcinoma, adenocarcinoma and large cell carcinoma were 35.7 (5/14), 45.5 (5/11) and 0.0% (0/1), respectively. The median survival time (MST) of all patients was 11 months. The MST for patients with stage III disease was 14 months; for those with stage IV disease it was 7 months. The MST for responding patients was 15 months and for not responding patients 5 months. Major toxicities were hematologic and gastrointestinal, and the dose-limiting factor was thrombocytopenia. This combination chemotherapy was effective against NSCLC with tolerable toxicities. Further trials are warranted to determine the efficacy of the combination chemotherapy. 相似文献
3.
The total volume change included gel and surrounded water with the swelling of five types of speherical cross-linked dextran (Sephadex) that are either nonionic (G) or possess one of four different ionic groups in the same molecular skeleton: CM: sodium carboxymethyl, SP: sodium sulphopropyl, DEAE: diethylaminoethyl chloride, and QAE: diethyl-(2-hydroxypropyl) aminoethyl chloride. All have been studied by dilatometry. The total volume decreased with the swelling of all Sephadexes. The maximum changes of total volume with the swelling in water were all negatives of CM, G, SP, (DEAE, QAE), which decrease in that order. These values did not depend on the concentration of sodium chloride and were closely related to the maximum heats of swelling. Total volume changes occurred by the dissociation of the ionic group of dextran derivatives that subtracted the total volume change due to hydration of Sephadex skeleton from the total volume change: ?21.6 ± 3.1 μL mmol?1 for CM, ?2.8 ± 8.0 μL mmol?1 for SP, +13.2 ± 4.4 μL mmol?1 for DEAE, and +15.4 ± 4.6 μL mmol?1 for QAE. These values are assumed to be reflected in the quantities of ions-water interaction of Sephadexes. © 1994 John Wiley & Sons, Inc. 相似文献
4.
Eri Chatani Keisuke Yuzu Yumiko Ohhashi Yuji Goto 《International journal of molecular sciences》2021,22(9)
Amyloid fibrils are supramolecular protein assemblies represented by a cross-β structure and fibrous morphology, whose structural architecture has been previously investigated. While amyloid fibrils are basically a main-chain-dominated structure consisting of a backbone of hydrogen bonds, side-chain interactions also play an important role in determining their detailed structures and physicochemical properties. In amyloid fibrils comprising short peptide segments, a steric zipper where a pair of β-sheets with side chains interdigitate tightly is found as a fundamental motif. In amyloid fibrils comprising longer polypeptides, each polypeptide chain folds into a planar structure composed of several β-strands linked by turns or loops, and the steric zippers are formed locally to stabilize the structure. Multiple segments capable of forming steric zippers are contained within a single protein molecule in many cases, and polymorphism appears as a result of the diverse regions and counterparts of the steric zippers. Furthermore, the β-solenoid structure, where the polypeptide chain folds in a solenoid shape with side chains packed inside, is recognized as another important amyloid motif. While side-chain interactions are primarily achieved by non-polar residues in disease-related amyloid fibrils, the participation of hydrophilic and charged residues is prominent in functional amyloids, which often leads to spatiotemporally controlled fibrillation, high reversibility, and the formation of labile amyloids with kinked backbone topology. Achieving precise control of the side-chain interactions within amyloid structures will open up a new horizon for designing useful amyloid-based nanomaterials. 相似文献
5.
The liver lipogenic enzymes are compared among rats, chickens, frogs and fish. Although the apparent Km values of glucose-6-phosphate
dehydrogenase for glucose-6-phosphate are not much different among all the species, those of malic enzyme for malate are much
higher in chickens and fish than in rats and frogs. Glucose-6-phosphate dehydrogenase showed very high activities compared
with malic enzyme in fish liver, and malic enzyme showed high activities in chicken liver. Although the apparent Km values
of acetyl-CoA carboxylase and fatty acid synthetase for substrates are in the same range among all the animals, the activity
of acetyl-CoA carboxylase seems to be extremely low in fish and frog livers, and that of fatty acid synthetase is low in frog
livers only. In addition, the apparent Km values of α-glycerophosphate acyltransferase of fish liver are very high, and the
enzyme activity appears to be extremely low compared to the others. Therefore, the enzymes at the first steps of both fatty
acid and glycerolipid syntheses of poikilothermos animals appear to be very low. On the other hand, the Ouchterlony double-diffusion
patterns showed that the lipogenic enzymes of chickens, frogs and fish are immunologically different from those of rats, with
the exception of acetyl-CoA carboxylase in chickens. Therefore, it is suggested that the fatty acid and glycerolipid forming
systems of poikilothermos animals are quite different from those of homoiothermos and the lipogenesis is very low in poikilothermos. 相似文献
6.
This paper is concerned with the stability analysis of a networked control system, wherein communication from the controller to the plant input is through a digital channel subject to packet-dropouts and finite-level quantization. No acknowledgments of receipt are available to the controller. To alleviate the effect of packet-dropouts, the controller transmits tentative plant input sequences. Within this setup, we derive a sufficient condition for small ?∞ signal ?∞ stability of the networked control system. This condition requires the maximum number of consecutive packet-dropouts to be bounded. We also elucidate the trade-off which exists between the disturbance attenuation and the step size of the quantizer and the maximum number of consecutive packet-dropouts. 相似文献
7.
Suharyanto Yamano Y. Kobayashi S. Michizono S. Saito Y. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2006,13(1):72-78
The breakdown of alumina rf windows is mostly caused by multipactor, as well as by material defects and contamination. Since multipator induces localized surface heating, leading to surface melting, it is necessary to observe secondary electron emission (SEE) coefficients of alumina ceramics under high temperature conditions. The SEE coefficients of commercial alumina ceramics and sapphire were measured by a scanning electron microscopy (SEM) with a single short-pulsed electron beam (100 pA, 1 ms) at room temperature and at 650degC. Additive materials used for sintering alumina, such as SiO 2 and MgO, were also investigated. Surface charging evaluations have also become important because the accumulated charges are discharged at the threshold Held, resulting in surface discharge. The surface charging evaluations were carried out by multi-pulse measurements with the injection of successive pulses on the sample. As a result, reductions in the SEE coefficients with temperature were confirmed, except for sapphire. The multi-pulse measurement results indicated that surface charging of the sapphire was higher than that of other samples. This may be one of the factors that causes sapphire not to be durable for rf window applications, compared with alumina ceramics. Although there are few exceptions, it was found that the SEE coefficients of alumina ceramics increased with the purity and the average grain size 相似文献
8.
Motonaka Kuroda Yumiko Kato Junko Yamazaki Naoko Kageyama Toshimi Mizukoshi Hiroshi Miyano Yuzuru Eto 《Food chemistry》2012
The determination of the kokumi peptide, γ-glutamyl-valyl-glycine (γ-Glu-Val-Gly) in raw scallop and processed scallop products was carried out using high pressure liquid chromatography–tandem mass spectrometry (LC/MS/MS). The detection of γ-Glu-Val-Gly was achieved using a multiple reaction monitoring (MRM) method. The optimised condition enabled the precise determination of γ-Glu-Val-Gly. Raw scallop contained 0.08 μg/g γ-Glu-Val-Gly, and the γ-Glu-Val-Gly levels in processed scallop products, such as dried-scallop and scallop extract, were measured to be 0.64 and 0.77 μg/g, respectively. This is the first report to confirm the existence of γ-Glu-Val-Gly in foodstuff. 相似文献
9.
Previous studies on polyamide 4, excellent properties, functionalities, and biodegradation in natural condition have been shown. In this study, three-branched (star-shaped) copolyamides constituted of polyamide 4 and polyamide 6 constitutional unit were synthesized by anionic ring-opening copolymerization of 2-pyrrolidone with ε-caprolactam. The thermal and mechanical properties and the biodegradability of the obtained copolyamides have been systematically investigated. The weight-average molecular weight of the copolyamides was as high as tens of thousands (Mw 10–80 × 103 g/mol). The composition of the copolyamides was approximately in accord with the monomer feed ratio, thereby being controllable. The thermal and mechanical properties changed readily as the composition was varied (Tm 146–266°C, ΔHm 10–70 J/g, Td 278–369°C, tensile strength 28–64 MPa, elongation at break 80–750%). The copolyamide having 2-pyrrolidone unit of 96–51 mol% exhibited biodegradability by an activated sludge. The biodegradation of the copolyamide proceeded uniformly without disproportion in constitutional unit. 相似文献
10.
Carbon coating of anatase-type TiO2 through their precipitation in PVA aqueous solution 总被引:1,自引:0,他引:1
Fine particles of photocatalytic anatase-type TiO2 prepared through hydrolysis of titanium-tetraisopropoxide were coated by carbon through their precipitation in poly(vinyl alcohol) (PVA) aqueous solution, followed by heat treatment at high temperatures of 400-1000 °C in a flow of high purity Ar. Without carbon coating, the phase transformation from anatase to rutile started above 600 °C, but it was suppressed up to 800 °C with carbon coating. Suppression of the phase transformation depended on the amount of carbon coated, apparent suppression being observed with carbon content above 5 mass%. The amount of carbon coated on anatase was controlled by changing the concentration of PVA in the solution. In order to have a carbon content of about 5 mass%, a PVA solution with more than 2 mass% had to be used. 相似文献