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81.
Fluorescent whitening agents in Tokyo Bay and adjacent rivers: their application as anthropogenic molecular markers in coastal environments 总被引:1,自引:0,他引:1
Two kinds of stilbene-type fluorescent whitening agents (i.e., DSBP and DAS1), minor components of laundry detergents, were analyzed in surface waters of Tokyo Bay and adjacent rivers and in sewage effluents to examine their usefulness as molecular markers in the marine environment. Sensitive determination using HPLC (high performance liquid chromatography) with fluorescence detection with postcolumn UV radiator was employed. DSBP and DAS1 were found in Tokyo rivers at concentrations of a few microg/L and approximately 1 microg/L, respectively. DSBP and DAS1 were widely distributed in Tokyo Bay waters at concentrations in the range of 0.019-0.264 microg/L and 0.021-0.127 microg/L, respectively. Comparison of these concentrations with those in sewage effluents (DSBP: 8 microg/L and DAS1: 2.5 microg/L on average) yielded sewage dilutions in Tokyo Bay on the order of 10(2). FWAs-salinity diagram in the Tamagawa Estuary showed fairly conservative behaviors of the FWAs with approximately 20% and approximately 10% removal of DSBP and DAS1, respectively. This is thought to be caused by photodegradation. The persistent nature of FWAs and their widespread distribution in coastal environments demonstrates the utility of FWAs in tracing the behavior of water from rivers and sewage outfalls. The DSBP/DAS1 ratio showed a decreasing trend from sewage effluents, to rivers, to Tokyo Bay, indicating selective photodegradation of DSBP. The DSBP/DAS1 ratio is proposed as an index of the degree of photodegradation and residence time and freshness of water mass in coastal environments. 相似文献
82.
Shinji Kanehashi Yuko Tomita Hiroshi Kawakita Shuichi Sato Tetsuo Miyakoshi Kazukiyo Nagai 《应用聚合物科学杂志》2013,129(4):2036-2045
Poly[methacryloxypropylheptacyclopentyl‐T8‐silsesquioxane (MAPOSS)‐co‐3‐methacryloxypropyltris(trimethylsiloxy)silane (SiMA)] was synthesized through free radical polymerization. The physical and carbon dioxide (CO2) sorption properties of the copolymer membranes were investigated in terms of the MAPOSS content. As the MAPOSS content increases, the membrane density increased, suggesting a decrease in the fractional free volume. In addition, the thermal stability was improved with increasing the MAPOSS content. These are because of the polyhedraloligomericilsesquioxane (POSS) units that restrict the high mobility of poly(SiMA) segments. The glass transition temperature, Tg of the copolymers was single Tg based on the differential scanning calorimetry, suggesting that the copolymers were random and not phase separation. Based on the CO2 sorption measurement, the POSS units play a role in reducing Henry's dissolution by suppressing the mobility of the poly(SiMA) component, while POSS units increase the nonequilibrium excess free volume, which contributes to the Langmuir dissolution. Based on these results, the introduction of MAPOSS unit is one of the effective ways to improved the thermal stability and CO2 sorption property due to the enhancement of the polymer rigidity. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
83.
Kalidas Shetty Masahiro Ohshima Taka Murakami Katsuji Oosawa Yuko Ohashi 《Food Biotechnology》2013,27(2):111-128
Abstract Melon (Cucumis melo L.) is an important fruit crop cultivated widely in every region of the world. Our laboratory is targeting this species for production of novel proteins important to food industry. Prior to expression of protein of interest in transgenic melon an efficient genetic transformation system has to be developed. In this context we are testing a wide variety of promoters fused to reporter gene for β‐glucuronidase (GUS) for expression specifically in melon fruits. In this study in melon, salicylic acid‐inducible promoter region of pathogenesis‐related protein gene (PR1a) of tobacco fused to β‐glucuronidase (GUS) gene was introduced into melon via Agrobacterium‐mediated gene transfer using a binary vector system. Gene transfer was effective when Agrobacterium virulence factors like acetosyringone (100 μM) and low pH (5.2) were provided during the co‐culture step. Transformed shoots were recovered from benzyladenine‐induced cut cotyledons using kanamycin gene as a selective marker. Regeneration of shoots from cotyledons was stimulated by providing 10 mM proline in the shoot organogenesis medium. Southern and Northern blot analysis of transformants confirmed the presence of β‐glucuronidase gene in two selected clones J‐3 and PR‐G. The transformants also showed high β‐glucuronidase activity after salicylic acid treatment. Thiamine, a previously known inducer of pathogenesis‐related protein, stimulated β‐glucuronidase in J‐3 but not PR‐G melon transformants tested in this study. These studies showed that tobacco PR1a promoter region can be expressed in melon and it was stimulated by salicylic acid. This indicates the potential to use the promoter region of tobacco PR1a for genetic improvement of melon for specific food processing‐related characteristics or for expression of novel food‐related proteins. The promoter region could be used to drive specific target genes under stress or salicylic acid induced conditions. 相似文献
84.
Hiroaki Anno Masahiro Hokazono Ritsuko Shirataki Yuko Nagami 《Journal of Electronic Materials》2013,42(7):2326-2336
The Al content dependence of crystallographic, thermoelectric, and mechanical properties is reported for polycrystalline Ba8Al x Si46?x (nominal x = 15 to 17) clathrates prepared by combining arc melting and spark plasma sintering methods. The elastic constants and the coefficient of thermal expansion (CTE), which are also important properties for designing thermoelectric devices, are presented. Powder x-ray diffraction, scanning electron microscopy, and energy-dispersive x-ray spectroscopy (EDX) indicate that the type I clathrate is the major phase of the samples but impurity phases (mainly BaAl2Si2, Si, and Al) are included in the samples with high Al contents. The actual Al content x determined by EDX ranges from approximately 14 to 15. The absolute value of the Seebeck coefficient increases and the electrical conductivity decreases as the Al content increases. The changes in Seebeck coefficient and electrical conductivity are explained in terms of the dependence of the carrier concentration on the Al content. The elastic constants and the CTE of the samples depend weakly on the Al content. Some of the properties are compared with reported data of single crystals of Ba8Al16Ge30, Ba8Ga16Ge30, Sr8Ga16Ge30, silicon, and germanium as standard references. The effective mass, Hall carrier mobility, and lattice thermal conductivity, which govern the transport properties, are determined to be ~ 2.4m 0, ~ 7 cm2 V?1 s?1, and ~ 1.3 W m?1 K?1, respectively, for actual Al content x of about 14.77. The thermoelectric figure of merit ZT is estimated to be about 0.35 at 900 K for actual Al content x of about 14.77. 相似文献
85.
Shuich Fujii Yuko Fukawa Hiroaki Takahashi Yosuke Inomata Kenichi Okada Kenji Fukui Katsuhiko Shirasawa 《Solar Energy Materials & Solar Cells》2001,65(1-4)
In 1996 a conversion efficiency of 17.1% had been obtained on 15 cm×15 cm mc-Si solar cell. In this paper, large-scale production technology of the high-efficiency processing will be discussed. Enlarging reactive ion etching (RIE) equipment size, technology of passivation, and fine contact grid with low resistance by screenprinted metallization, which is firing through PECVD SiN, have been investigated. 相似文献
86.
Lipase from Candida antarctica was entrap-immobilized in cellulose acetate-TiO2 gel fiber (fiber-immobilized lipase) by the sol-gel method. Syntheses of geranyl acetate and citronellyl acetate catalyzed
by the fiber-immobilized lipase were studied in heptane solution. Conversions reached 85% for geranyl acetate after 100 h,
and 75% for citronellyl acetate after 80 h, and these values were almost identical to those for syntheses catalyzed by nonimmobilized
lipase, although the reaction rate was decreased by immobilization. Compared to those of the non-immobilized lipase and commercially
available immobilized lipase (Novozyme 435), the activity of the fiber-immobilized lipase was not particularly affected by
changes in reaction conditions, such as bulk water content or substrate concentration. The fiber-immobilized lipase retained
a high level of activity after six repeated uses, and almost no enzyme leakage from fiber was observed. However, the reactivity
of the fiber-immobilized lipase was depressed at higher temperature, presumably due to dehydration by thermal contraction
of the gel fiber. 相似文献
87.
Kaoru Kohyama Yuko Nakayama Hirotaka Watanabe Tomoko Sasaki 《Journal of food science》2005,70(4):S257-S261
ABSTRACT: The mastication of 7 differently prepared apple samples (raw pieces peeled and unpeeled, sliced, grated, cooked pieces with and without peel, and half-cooked pieces, 10 g each) was evaluated using electromyography (EMG). Eleven subjects participated in the EMG recording of both sides of the masseter and temporal muscles while eating samples normally. Only the grated sample reduced the number of chewing strokes and muscle activity before swallowing. In contrast, the thin apple slices produced significantly shorter contraction duration and cycle time only during the 1st 5 chewing strokes. The EMG duration and cycle in subsequent chews, as well as the other parameters, did not significantly differ between slices and pieces. Cooked apples exhibited significantly lower EMG amplitude and muscle activity per chew than their raw counterparts; however, there was no evidence of reduced total muscle activity required for swallowing. Raw and cooked apples with peel yielded significantly greater EMG amplitude and longer duration than those without peel. These findings suggest that appropriate preparation is necessary for people with various mastication abilities: grated for very low ability, cooked for those with weak chewing force, and unpeeled for mastication training. 相似文献
88.
89.
We investigate a biologically inspired design of an interface agent that is embedded inside human-artifact interactions rather
than as an external observer, and has to work as an intelligent associate for a human user/operator in a time-critical situation
like in an emergency. First, recent paradigmatic shifts of artifact design principles are discussed from an interdisciplinary
viewpoint. Then, after the idea of Clancey’s activity modeling, we discuss the design principles of a situated interface agent.
That is, different from the conventional supervisory agent’s task of seeking to optimize an isolated control task, such an
agent has to be able to maintain its identity as an organism living within multiple contexts and looking inwards to consider
the the nature of memory and perception, and looking outwards to consider the nature of social action with a human operator.
Initially, our prior work using such a design principle is presented, and then decision-theoretic formulations of an interface
agent’s activities are provided.
This work was presented, in part, at the Third International Symposium on Artificial Life and Robotics, Oita, Japan, January
19–21, 1998 相似文献
90.
Yuko Hasegawa 《溶剂提取与离子交换》2019,37(3-4):245-258
ABSTRACTSince a particular trivalent lanthanide (Ln(III)) often plays a unique role in different industrial applications, the development of a selective separation method to get only the requisite Ln(III) would be most convenient. Synergistic extraction with β-diketone (HA) and Lewis base (B), which has been extensively used for the separation of lanthanides, relies on two processes: the extraction with HA as LnA3 into the organic phase and the complexation of LnA3 with B as LnA3B in the organic phase. The variation in the pattern of the extraction constants of LnA3 across the Ln series correlates with the number of CF3- group in the β-diketones, and with the stability constants of LnA3B of different Lewis bases. It is seen that the constants with bipyridyl increase with increasing atomic number, while those with POPO (methylenediphosphonate) and MePhPA (methylphenylphenanthroline carboxamide) decrease with increasing Ln atomic number. Using pivaloyltrifluoroacetone as the β-diketone and MePhPA, the best extractability appeared at Sm(III) among the series. As a conclusion, to get only a required Ln(III), the combination of β-diketone and Lewis base is very important. In addition, the separation of Lns(III) from other metals and the use of new extractants developed recently and reported in literature were referred to find out more effective extractants and selective separation methods. 相似文献