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排序方式: 共有1784条查询结果,搜索用时 15 毫秒
101.
Yoshifumi Atsushi Wataru Fumihiro Junji Hiroaki 《Sensors and actuators. B, Chemical》2009,140(2):649-655
A novel method for exchanging solutions used in biochemical analyses and a device to carry out the exchange are proposed. An array of plugs formed using six injectors was transported in a microflow channel using a main pump located at one end of the main flow channel. The injectors and main pump were operated on the basis of the change in volume caused by the electrolysis of water. Bubbles were produced from working electrodes; these bubbles caused a diaphragm placed below the injectors to inflate and occlude the inlet of the solution reservoir. Increase in the number of bubbles caused the reservoir to inject the solution into the main flow channel in the form of a plug. Each plug was individually transported downstream to the sensing area by the main pump, which was operated in a similar manner to the injector. The device was used for the detection of a tumor marker, α-fetoprotein (AFP). Plugs of necessary solutions were individually transported to the sensing area with immobilized primary antibodies to allow antigen–antibody binding, cleaning, and detection. The fluorescence intensity from the antibodies showed clear dependence on the concentration of AFP. The immobilization of antibodies could also be carried out on-chip. 相似文献
102.
This paper considers product mix problems including randomness of future returns, ambiguity of coefficients and flexibility of upper value with respect to each constraint such as budget, human resource, time and several costs. Particularly, the flexibility is assumed to be a fuzzy goal. Then, several models based on maximizing total future profits under a level of satisfaction to each fuzzy goal are proposed. Furthermore, the model considering preference ranking to each fuzzy goal of constraints is proposed. Since these problems are basically formulated as nonlinear programming problems, the transformations into deterministic equivalent problems are introduced and the efficient solution methods are developed. A numerical example for product mix problem is given to illustrate our proposed models. 相似文献
103.
Kawashima Y Nagashima Y Shiomi K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(6):385-388
Salivary glands from 29 species of marine carnivorous gastropods in nine families were examined for lethal activity against mice and tetramine content. Mouse lethality was assayed by intravenous injection of buffer extracts into mice, and was detected in 14 species. Heat-stability tests confirmed that toxins in four species were thermolabile, while those in eight species were thermostable. Based on the tetramine contents determined by the colorimetric method using methanolic extracts, the thermostable toxins in seven species (Neptunea eulimatalamellosa, N. vinosa, N. arthritica, N. bulbacea, N. intersculpta f. pribiloffensis, N. intersculpta f. frater pilsbry and Hemifusus tuba) were considered to be tetramine contained at high levels (more than 900 micrograms/g salivary gland), but that in one species (Buccinum opisthoplectum) appeared to be a low-molecular-weight compound differing from tetramine. It is interesting that one (Hemifusus tuba) of the seven species containing high amounts of tetramine belongs to the family Melongenidae, although the other six Neptunea species are members of the family Buccinidae, as expected from previous studies. 相似文献
104.
A study was made to investigate an optimum condition for ruthenium tetraoxide staining of poly(butylene terephthalate) (PBT) with glass transition temperature as low as ca. 23 degrees C for TEM observation of melt-grown PBT crystals. The morphological study of ultrathin sections prepared based on optimum staining at 25 degrees C for 8 h revealed formation of fringed-micellar crystal nuclei in the early stage and folded-chain fringed-micellar crystals in the later stage of isothermal crystallization at 40 degrees C from melt. The fraction of chain-folded crystals increased with increasing crystallization temperature from the quantitative analysis of crystal thickness in comparison with the reported morphology using the replica method. 相似文献
105.
Sudo J Iwase H Higashiyama K Kakuno K Miyasaka F Meguro T Takayama K 《Drug development and industrial pharmacy》2002,28(1):59-65
To increase delivery of L-dopa in its transdermal absorption, a new lipophilic derivative of L-dopa, L-dopa-butylester, was synthesized. An in-vitro study employing two-chamber diffusion cells, in which the excised rat abdominal skin was mounted, revealed that, in the presence of L-menthol and ethanol, L-dopa-butylester penetrated in its original form more effectively than L-dopa. L-Dopa-butylester sheets were made by immersing wiper sheets in methanol containing the compound, and then evaporating the methanol. An extraction study of the compound from the sheets revealed that its stability was maintained for at least 12 weeks. In an in-vivo cutaneous absorption study, an L-dopa-butylester sheet was attached to the shaved rat abdominal skin. A hydrogel containing L-menthol and ethanol was spread on vinyl tape, and this sheet was placed over it. In plasma, the L-dopa level rose linearly between 30 and 180 min after the cutaneous application; L-dopa-butylester was not detected. The L-dopa level was higher than that in which L-dopa was applied. These findings indicated that the lipophilic nature of L-dopa-butylester further increased its penetration through the skin, and that L-dopa-butylester that was taken up into the general circulation system was rapidly converted to L-dopa by hydrolysis in the body. 相似文献
106.
Hiroaki Matsumoto Sadao Watanabe Naoya Masahashi Shuji Hanada 《Metallurgical and Materials Transactions A》2006,37(11):3239-3249
The Young’s modulus of Ti-V and Ti-V-Sn alloys quenched from the β-phase region after solution treatment and cold rolling
was investigated in relation to alloy compositions, microstructures, and constituent phases. The composition dependence of
the Young’s modulus for quenched Ti-V binary alloys shows two minima of 69 GPa at Ti-10 mass pct V and 72 GPa at Ti-26 mass
pct V. Between the two compositions, athermalω or stress-induced ω is introduced in retainedβ phase and increases Young’s modulus. That is, a low Young’s modulus is attained unless alloys undergoω transformation. In Ti-5 and -8 mass pct V, which under goα′ (hcp) martensitic transformation on quenching, the Young’s modulus further decreases by cold rolling, which can be reasonably
explained by the formation ofα′ rolling texture. Comparing Young’s modulus in Ti-V binary alloy with that in Ti-Nb binary alloy, it is found that Young’s
modulus is remarkably increased by athermal- or stress inducedω phase, and it shows a minimum when both martensitic andω transformation are suppressed during quenching in metastableβ alloys. The Sn addition to Ti-V binary alloy retards or suppresses athermal and stress-inducedω transformation, thereby decreasing Young’s modulus. Young’s modulus exhibits minimum values of 51 GPa in quenched (Ti-12
pct V)-2 pct Sn and of 57 GPa in cold-rolled (Ti-12 pct V)-6 pct Sn. 相似文献
107.
JM Mariner JB McMahon BR O'Keefe K Nagashima MR Boyd 《Canadian Metallurgical Quarterly》1998,248(3):841-845
Concentrations of the potent, HIV(human immunodeficiency virus) inactivating protein, cyanovirin-N (CV-N), which completely inhibit HIV-1 infectivity, do not block the binding of soluble CD4-receptor (sCD4) to HIV-1 lysates nor the attachment of intact HIV-1 virions to several target T-cell lines. Furthermore, in contrast to the known disassociative effects of sCD4 on viral envelope glycoproteins, treatment of HIVRF with high concentrations of CV-N results in complete viral inactivation but without apparent shedding of gp120 or other ultrastructural changes. These results are consistent with the view that the virucidal effects of CV-N result from interference with step(s) in the fusion process subsequent to the initial binding of the virus to target cells. 相似文献
108.
Reversible crosslinking in cellulose. I. Determination of mercaptan and disulfide in modified cotton
Mercaptan and disulfide contents of modified cotton fabrics could be determined by application of Leach's polarographic method for wool, with minor modification. It was found that mercaptocellulose prepared by the reaction of tosyl cellulose and potassium thiolacetate followed by alkaline hydrolysis contained considerable amounts of disulfided in addition to mercaptain. Iodometric titration of mercaptocellulose gave a higher value of mercaptan than that obtained by the polarographic method. The mercaptan and disulfide contents and methylene blue uptake of the iodine-treated samples indicate that some of the mercaptan groups further undergo oxidation to acidic groups as a result of the iodine treatment. The spatial effect in the oxidation of mercapto groups in modified cotton is briefly discussed. 相似文献
109.
Tagawa Hiroaki 《Journal of Nuclear Materials》1974,51(1):78-89
The present state of knowledge of the phase relations and thermodynamic properties of the uranium-nitrogen system is given. Emphasis is placed on the nonstoichiometric and thermodynamic properties of uranium sesquinitride. The present paper consists of two parts. The first part is on the phase relations; an equilibrium phase diagram is proposed, and the relationship between structure and lattice parameter for the α-U2N3-UN2 system is shown. The second part deals with thermodynamic properties of UN and α-U2N3; the data on decomposition pressures, specific heats, and heats and free energies of formation are summarized and evaluated. 相似文献
110.
Activated carbon adsorption of trichloroethylene (TCE) vapor stripped from TCE-contaminated water 总被引:1,自引:0,他引:1
Ground water contaminated with trichloroethylene (TCE) used in electronic, electric, dry cleaning and the like industries is often treated by air-stripping. In this treatment process, TCE in its vapor form is stripped from ground water by air stream and sometimes emitted into the atmosphere without any additional treatments. Activated carbon adsorption is one of the practical and useful processes for recovering the TCE vapor from the exhaust air stream. However, adsorption of the TCE vapor from the stripping air stream onto activated carbons is not so simple as that from dry air, since in the exhaust air stream the TCE vapor coexists with water vapor with relatively high concentrations. The understanding of the adsorption characteristics of the TCE vapor to be adsorbed on activated carbon in the water vapor-coexisting system is essential for successfully designing and operating the TCE recovery process. In this work, the adsorption equilibrium relations of the TCE vapor adsorption on activated carbons were elucidated as a function of various relative humidity. Activated carbon fibers (ACFs) were used as model activated carbon. The adsorption equilibrium relations were studied by the column adsorption method. The adsorption isotherms of TCE vapor adsorbed on sample ACFs were successfully correlated by the Dubinin-Radushkevich equation for both cases with and without coexistent water vapor. No effects of coexistent water vapor were found on the limiting adsorption volume. However, the adsorption characteristic energy was significantly reduced by the coexistence of water vapor and its reduction was successfully correlated with the equilibrium amount of water vapor adsorbed under the dynamic condition. 相似文献