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1.
On the heat removal characteristics and the analytical model of a thermal energy storage capsule using gelled Glauber's salt as the PCM 总被引:1,自引:0,他引:1
Akio Saito Seiji Okawa Tadafumi Shintani Ryuichiro Iwamoto 《International Journal of Heat and Mass Transfer》2001,44(24):4693-4701
An analytical and experimental investigation was performed on a heat removal process of the thermal energy storage (TES) capsule, using gelled Glauber's salt. Transient heat flux at the capsule wall was measured for various cooling conditions. In cases where the initial temperature was lower than the saturation temperature of the phase change material (PCM), numerical analyses were performed, approximating the process by a relaxation phenomenon where crystals grew around crystal nuclei. The results of the numerical solution agreed very well with the experimental results. 相似文献
2.
Reactions of three kind of syringylglycerol- β-syringyl ether type model compounds under alkaline medium were investigated. Sinapyl alcohol and β-hydroxypropiosyringone were formed as phenyl propanoid moieties from syringylglycerol- β-(methyl-syringyl) ether 1 by the β-aryl ether cleavage under soda treatment, while only sinapyl alcohol was formed from syringylglycerol- β-syringyl ether 2. The formation of both two degradation products are quite interesting because there is no nucleophilic additives in soda liquor. A possible reaction mechanisms for the β-aryl cleavage of syringylglycerol-β-syringyl ether type is homolytical cleavage via quinone methide. 相似文献
3.
The subfamily Geometrinae (Lepidoptera: Geometridae) includes many species called emerald moths. Based on our recent finding
of novel polyenyl compounds, including a double bond at the 12-position from two geometrine species, Hemithea tritonaria and Thalassodes immissaria intaminata, (6Z,9Z,12Z)-6,9,12-trienes and (3Z,6Z,9Z,12Z)-3,6,9,12-tetraenes with a C17–C20 straight chain were synthesized and analyzed by GC-MS. The 6,9,12-trienes, which were prepared by a double Wittig reaction
between two alkanals and an ylide derived from (Z)-1,6-diiodo-3-hexene, characteristically produced fragment ions at m/z 79, 150, and M–98. The 3,6,9,12-tetraenes, which were prepared by a coupling between (Z)-3-alkenal and an ylide derived from (3Z,6Z)-1-iodo-3,6-nonadiene, showed fragment ions at m/z 79, 148, and M–96. These diagnostic ions were useful to distinguish these compounds from other known polyenyl pheromones,
such as 4,6,9- and 6,9,11-trienes and 1,3,6,9-tetraenes. With reference to the GC-MS data, pheromone extracts of other species
in Geometrinae inhabiting the Iriomote Islands were analyzed, and the 6,9,12-trienes were identified in the pheromone gland
extracts of Pamphlebia rubrolimbraria rubrolimbraria and Maxates versicauda microptera. Furthermore, a field evaluation of the synthetic polyenes in a mixed forest of Tokyo revealed the following new male attractants
for emerald moths: Idiochlora ussuriaria by a C17 6,9,12-triene and Jodis lactearia by a C20 3,6,9,12-tetraene, indicating the characteristic chemical structures of Geometrinae pheromones. On the other hand, through
reexamination of the pheromone extract of H. tritonaria, (3E,6E)-α-farnesene was identified as an electrophysiologically active component in addition to the C17 6,9,12-triene. The binary mixture attracted more males than the single component lure baited with the triene in the Iriomote
Islands. 相似文献
4.
Keiji Uchiyama Hideyuki Hara Junji Chida Agriani Dini Pasiana Morikazu Imamura Tsuyoshi Mori Hanae Takatsuki Ryuichiro Atarashi Suehiro Sakaguchi 《International journal of molecular sciences》2021,22(21)
Prion diseases are a group of fatal neurodegenerative disorders caused by accumulation of proteinaceous infectious particles, or prions, which mainly consist of the abnormally folded, amyloidogenic prion protein, designated PrPSc. PrPSc is produced through conformational conversion of the cellular isoform of prion protein, PrPC, in the brain. To date, no effective therapies for prion diseases have been developed. In this study, we incidentally noticed that mouse neuroblastoma N2a cells persistently infected with 22L scrapie prions, termed N2aC24L1-3 cells, reduced PrPSc levels when cultured in advanced Dulbecco’s modified eagle medium (DMEM) but not in classic DMEM. PrPC levels remained unchanged in prion-uninfected parent N2aC24 cells cultured in advanced DMEM. These results suggest that advanced DMEM may contain an anti-prion compound(s). We then successfully identified ethanolamine in advanced DMEM has an anti-prion activity. Ethanolamine reduced PrPSc levels in N2aC24L1-3 cells, but not PrPC levels in N2aC24 cells. Also, oral administration of ethanolamine through drinking water delayed prion disease in mice intracerebrally inoculated with RML scrapie prions. These results suggest that ethanolamine could be a new anti-prion compound. 相似文献
5.
Toshihiro Nagao Yuji Shimada Yoshie Yamauchi-Sato Takaya Yamamoto Masaaki Kasai Kentaro Tsutsumi Akio Sugihara Yoshio Tominaga 《Journal of the American Oil Chemists' Society》2002,79(3):303-308
A commercial product of CLA contains almost equal amounts of cis-9,trans-11 (c9,t11)-CLA and trans-10,cis-12 (t10,c12)-CLA. We attempted to enrich the two isomers by a two-step selective esterification using Candida rugosa lipase that acted on c9,t11-CLA more strongly than on t10,c12-CLA. An FFA mixture containing CLA isomers was esterified with an equimolar amount of lauryl alcohol in a mixture of 20%
water and the lipase. When the esterification of total FA reached 50%, two isomers were fractionated in a good yield: t10,c12-CLA was enriched in FFA, and c9,t11-CLA was recovered in lauryl esters. The FFA were esterified again to enrich t10,c12-CLA. At 27.3% esterification of total FA, the t10,c12-CLA content in FFA increased to 64.8 wt% with 89.3% recovery: The ratio of the content of t10,c12-CLA to that of two isomers was 95.9%. Lauryl esters obtained by the single esterification were employed for enrichment
of c9,t11-CLA. After the esters were hydrolyzed, the resulting FFA were esterified again with lauryl alcohol. At 62.0% esterification
of total FA, the c9,t11-CLA content in lauryl esters increased to 73.3 wt% with 79.4% recovery: The ratio of the content of c9,t11-CLA to that of two isomers was 95.6%. In a 600-g-scale purification, molecular distillation was effective in separating
the reaction mixture into lauryl alcohol, FFA, and lauryl ester fractions. 相似文献
6.
Yasumasa?Minemoto Shuji?AdachiEmail author Yuji?Shimada Toshihiro?Nagao Toshio?Iwata Yoshie?Yamauchi-Sato Takaya?Yamamoto Tadashi?Kometani Ryuichi?Matsuno 《Journal of the American Oil Chemists' Society》2003,80(7):675-678
The autoxidation processes of the cis-9,trans-11 (c9,t11) and trans-10,cis-12 (t10,c12) isomers of CLA were separately observed at ca. 0% RH and different temperatures. The t10,c12 CLA oxidized faster than the c9,t11 isomer at all tested temperatures. The first half of the oxidation process of t10,c12 CLA obeyed an autocatalytic-type rate expression, but the latter half followed first-order kinetics. On the other hand,
the entire oxidation process of c9,t11 CLA could be expressed by the autocatalytic-type rate expression. The apparent activation energies and frequency factors
for the autoxidation of the isomers were estimated from the rate constants obtained at various temperatures based on the Arrhenius
equation. The apparent activation energies for the CLA isomers were greater than those for the nonconjugated n−6 and n−3 PUFA
or their esters. However, the enthalpyentropy compensation held during the autoxidation of both the CLA and PUFA. This suggested
that the autoxidation mechanisms for the CLA and PUFA were essentially the same. 相似文献
7.
Solid-state structures and crystallization kinetics were compared between poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [PHB-HV] and PHB/PHB-HV blends exhibiting the cocrystallization. As cocrystallizable blends, both the blends showing complete cocrystallization, i.e. the PHB content in the crystalline phase is the same as that of the whole blends, and the blends forming a PHB-rich crystalline phase were used. The PHB and HV content in the cocrystalline phase were determined by high-resolution solid-state 13C NMR spectroscopy. In order to determine these contents with a minimum experimental error, site-specific 13C-labeled PHB/PHB-HV blends and PHB-HV copolymers were used. The crystallinity, lamellar structures, spherulite growth rate, and melting behavior were analyzed by wide-angle X-ray diffraction, small-angle X-ray scattering, polarized microscope, and differential scanning calorimetry, respectively. In these data, no difference was observed between the complete-cocrystallizable PHB/PHB-HV blends and the PHB-HV copolymers with the same overall HV content. On the other hand, the PHB/PHB-HV blends forming a PHB-rich crystalline phase has the amorphous layers thicker than that of the PHB-HV copolymers with the same overall HV content. Based on the collected data, the similarity and differences in the solid-state structures and properties between PHB-HV copolymers and cocrystallizable PHB/PHB-HV blends were discussed. 相似文献
8.
Takumi Watanabe Yong He Naoki Asakawa Naoko Yoshie Yoshio Inoue 《Polymer International》2001,50(4):463-468
The specific interactions between several low‐molecular‐weight diamino compounds and poly(ε‐caprolactone) (PCL) have been investigated by FT‐IR. It was found that PCL and 3,3′‐diaminodiphenylmethane (3,3′‐DADPM) interact through strong intermolecular hydrogen bonds in the blend. Thermal and mechanical properties of PCL/3,3′‐DADPM blends were investigated by DSC and tensile measurements, respectively. The glass transition temperature of the blend increases while both the melting point and the elongation‐at‐break of the blend decrease with the increase of 3,3′‐DADPM content. Besides 3,3′‐DADPM, several other low‐molecular‐weight compounds containing two amino groups, such as o‐phenylenediamine or 1,6‐diaminohexane, were also added into PCL and the corresponding blend systems were investigated by FT‐IR and DSC. The effect of the chemical structure of the additives on the properties of PCL is discussed. © 2001 Society of Chemical Industry 相似文献
9.
Novel vitamin E derivative with 4-substituted resorcinol moiety has both antioxidant and tyrosinase inhibitory properties 总被引:3,自引:0,他引:3
A novel vitamin E derivative, (6″-hydroxy-2″,5″,7″,8″-tetramethylchroman-2″-yl) methyl 3-(2′,4′-dihydroxyphenyl)propionate
(TM4R), which has a chromanoxyl ring and 4-substituted resorcinol moieties, was synthesized; and its inhibitory effects on
tyrosinase, antioxidant ability, and lightening effect of ultraviolet B (UVB)-induced hyperpigmentation were estimated. TM4R
showed potent inhibitory activity on tyrosinase, which is the rate-limiting enzyme in melanogenesis. The scavenging activities
of TM4R on 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals were found to be nearly the same as those of α-tocopherol.
Furthermore, an efficient lightening effect was observed following topical application of TM4R to UVB-stimulated hyperpigmented
dorsal skin of brownish guinea pigs. These results suggest that TM4R may be a candidate for an efficient whitening agent,
possibly by inhibiting tyrosinase activity and biological reactions caused by reactive oxygen species. 相似文献
10.
A -conjugated polymer, poly(pyridine-2,5-diyl) (PPy) was investigated as a support for CuCl2 in the synthesis of dimethyl carbonate by oxidative carbonylation of methanol. The PPy–CuCl2 adduct had high catalytic activity which was comparable to that of the homogeneous CuCl2 catalyst. The adduct caused corrosion of stainless-steel vessels only to minor extent, compared with the homogeneous CuCl2 catalyst. This PPy–CuCl2 catalyst was easily recycled by filtration and showed a similar catalytic activity in the third time use. The presence of the -conjugated system in PPy, through which electrons can move, may bring about the high catalytic activity for the oxidative carbonylation of methanol, which involves Cu(II)/Cu(I) redox processes. 相似文献