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121.
QiuHong Wang Abdusalam Abdukerim Wei Chen Xun Chen YunHua Chen XiangYi Cui YingJie Fan DeQing Fang ChangBo Fu LiSheng Geng Karl Giboni Franco Giuliani LinHui Gu XuYuan Guo Ke Han ChangDa He Di Huang Yan Huang YanLin Huang Zhou Huang Peng Ji XiangDong Ji YongLin Ju YiHui Lai Kun Liang HuaXuan Liu JiangLai Liu WenBo Ma YuGang Ma YaJun Mao Yue Meng Parinya Namwongsa KaiXiang Ni JinHua Ning XuYang Ning XiangXiang Ren ChangSong Shang Lin Si AnDi Tan AnQing Wang HongWei Wang Meng Wang SiGuang Wang XiuLi Wang Zhou Wang MengMeng Wu ShiYong Wu JingKai Xia MengJiao Xiao PengWei Xie BinBin Yan JiJun Yang Yong Yang ChunXu Yu Jumin Yuan Dan Zhang HongGuang Zhang Tao Zhang Li Zhao QiBin Zheng JiFang Zhou Ning Zhou XiaoPeng Zhou 《中国科学:物理学 力学 天文学(英文版)》2020,(3):54-63
In dark matter direct detection experiments,neutron is a serious source of background,which can mimic the dark matter-nucleus scattering signals.In this paper,we present an improved evaluation of the neutron background in the PandaX-II dark matter experiment by a novel approach.Instead of fully relying on the Monte Carlo simulation,the overall neutron background is determined from the neutron-induced high energy signals in the data.In addition,the probability of producing a dark-matter-like background per neutron is evaluated with a complete Monte Carlo generator,where the correlated emission of neutron(s)andγ(s)in the(α,n)reactions and spontaneous fissions is taken into consideration.With this method,the neutron backgrounds in the Run 9(26-ton-day)and Run 10(28-ton-day)data sets of PandaX-II are estimated to be(0.66±0.24)and(0.47±0.25)events,respectively. 相似文献
122.
J. Mullens A. Vos A. De Backer D. Franco J. Yperman L. C. Van Poucke 《Journal of Thermal Analysis and Calorimetry》1993,40(1):303-311
The 124 superconductor YBa2Cu4O8 was prepared from the oxalate precursor Y2(C2O4)3. ·4BaC2O4·8CuC2O4·xH2O at one atmosphere oxygen pressure. In O2 the precursor decomposes in one step at 300°C and more gradually (300°–600°C) in Ar. The stability of the superconductor is strongly dependent on the gas atmosphere: in O2 and in air there is no significant weight change as long as the temperature does not exceed 800°C, whereas in a 1% O2-99%N2 mixture decomposition starts at about 670°C with the formation of CuO and YBa2Cu3Ox withx<7. The reduction of YBa2Cu4O8 in a 5% H2-95% Ar mixture takes place in at least four major steps with formation of products such as Y2O3, BaO, Cu2O, Cu, BaY2O4 and Ba4Y2O7. 相似文献
123.
Angela Lopedota Adriana Trapani Annalisa Cutrignelli Valentino Laquintana Nunzio Denora Massimo Franco Giuseppe Trapani Gaetano Liso 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):425-432
The objective of this work was to develop a novel microparticulate system based on the mucoadhesive polymer Eudragit-RS 100
and cyclodextrins (CDs), potentially useful for the oral administration of Glutathione (γ–glutamylcysteinylglycine, GSH).
For this purpose, an oil-in-oil (O/O) emulsion-solvent evaporation method was used for the preparation of microparticles (MPs)
containing GSH alone or together with one of the following CDs: α-, β-, γ-, methyl-β-(Me-β-), hydroxypropyl-β-(HP-β-) or sulfobutylether-β-cyclodextrin
(SBE7m-β-CD). MPs were obtained by emulsifying a mixture of Eudragit RS 100, GSH, CD and magnesium stearate in acetone or acetonitrile
with a mixture of liquid paraffin and Span 80. Size, encapsulation efficiency, and drug release of the prepared MPs were evaluated.
The results clearly indicated that all the examined properties were dependent on the water-miscible solvents and CD used.
In particular, MPs prepared by using acetone or acetonitrile showed different size distributions with mean diameters in the
ranges 82–350 and 15–22 μm, respectively. Moreover, encapsulation efficiency values were found to be high in all cases (71–99%)
and was significantly affected by the CD type. The GSH release rates were evaluated employing dissolution media with different
pH values (1.2, 6.8 and 7.4) and the following rank order was obtained for MPs prepared using acetone: MPs incorporating Me-β-CD > MPs
without CD > MPs incorporating the remaining CDs. On the other hand, MPs prepared using acetonitrile gave the highest GSH
release rate. Finally, stability of GSH encapsulated in MPs containing HP-β-CD to enzymatic attack by pepsin A, α-chymotrypsin,
and γ-glutamyltranspeptidase was also investigated. 相似文献
124.
Application of the assay of aflatoxins by liquid chromatography with fluorescence detection in food analysis 总被引:2,自引:0,他引:2
Jaimez J Fente CA Vazquez BI Franco CM Cepeda A Mahuzier G Prognon P 《Journal of chromatography. A》2000,882(1-2):1-10
HPLC using fluorescence detection has already become the most accepted method for the determination of aflatoxins due to its several advantages over other analytical methods. Both normal- and reversed-phase HPLC can be used. However the reversed-phase HPLC methods are more popular. Liquid chromatographic determination of aflatoxins using fluorescence detection and its application in food analysis is reviewed in this article. 相似文献
125.
Merlin C. E. Bandeira César V. Franco Emilse Martini 《Journal of Solid State Electrochemistry》1999,3(4):210-214
The present study focuses on the electronic and electrochemical features of a copolymer electrochemically grown from pyrrole
and trans-[RuCl2(pmp)4] monomers, where pmp = 3-(pyrrol-1-ylmethyl)pyridine. The results from electrochemical impedance spectroscopy analyses revealed
the redox behavior of the poly{pyrrole-trans-[RuCl2(pmp)4]} compound as well as the non-homogeneous nature of the extremely thin polymeric layers. An equivalent circuit is proposed
for an optimized film produced under the scope of the work.
Received: 4 May 1998 / Accepted: 24 August 1998 相似文献
126.
Valentina Laghezza Masci Anna‐Rita Taddei Thomas Courant Ozgül Tezgel Fabrice Navarro Franco Giorgi Denis Mariolle Anna‐Maria Fausto Isabelle Texier 《Macromolecular bioscience》2019,19(5)
Curcumin‐loaded collagen cryostructurates have been devised for wound healing applications. Curcumin displays strong antioxidant, antiseptic, and anti‐inflammatory properties, while collagen is acknowledged for promoting cell adhesion, migration and differentiation. However, when curcumin is loaded directly into collagen hydrogels, it forms large molecular aggregates and clogs the matrix pores. A double‐encapsulation strategy is therefore developed by loading curcumin into lipid nanoparticles (LNP), and embedding these particles inside collagen scaffolds. The resulting collagen/LNP cryostructurates have an optimal fibrous structure with ≈100 µm average pore size for sustaining cell migration. Results show that collagen is structurally unaltered and that nanoparticles are homogeneously distributed amidst collagen fibers. Hydrogels soaked in saline buffer release about 20 to 30% of their nanoparticles content within 24 h, while achieved 100% release after 25 days. When exposed to NIH 3T3 fibroblasts, these hydrogels provide a satisfactory scaffold for cell interaction as early as 4 h after seeding, with no cytotoxic counter effect. These positive features make the collagen/lipid cryostructurates a promising material for further use in wound healing. 相似文献
127.
Emission of volatile sesquiterpenes and monoterpenes in grapevine genotypes following Plasmopara viticola inoculation in vitro 下载免费PDF全文
Alberto Algarra Alarcon Valentina Lazazzara Luca Cappellin Pier Luigi Bianchedi Rainer Schuhmacher Georg Wohlfahrt Ilaria Pertot Franco Biasioli Michele Perazzolli 《Journal of mass spectrometry : JMS》2015,50(8):1013-1022
The grapevine (Vitis vinifera) is one of the most widely cultivated fruit crops globally, and one of its most important diseases in terms of economic losses is downy mildew, caused by Plasmopara viticola. Several wild Vitis species have been found to be resistant to this pathogen and have been used in breeding programs to introduce resistance traits to susceptible cultivars. Plant defense is based on different mechanisms, and volatile organic compounds (VOCs) play a major role in the response to insects and pathogens. Although grapevine resistance mechanisms and the production of secondary metabolites have been widely characterized in resistant genotypes, the emission of VOCs has not yet been investigated following P. viticola inoculation. A Proton Transfer Reaction‐Time of Flight‐Mass Spectrometer (PTR‐ToF‐MS) was used to analyze the VOCs emitted by in vitro‐grown plants of grapevine genotypes with different levels of resistance. Downy mildew inoculation significantly increased the emission of monoterpenes and sesquiterpenes by the resistant SO4 and Kober 5BB genotypes, but not by the susceptible V. vinifera Pinot noir. Volatile terpenes were implicated in plant defense responses against pathogens, suggesting that they could play a major role in the resistance against downy mildew by direct toxicity or by inducing grapevine resistance. The grapevine genotypes differed in terms of the VOC emission pattern of both inoculated and uninoculated plants, indicating that PTR‐ToF‐MS could be used to screen hybrids with different levels of downy mildew resistance. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
128.
Kobra Mahdavipour Mahshid Khazaei Shadfar Hossein Rangani Jahromi Roberto Morandotti Rosario Lo Franco 《Entropy (Basel, Switzerland)》2022,24(3)
A witness of non-Markovianity based on the Hilbert–Schmidt speed (HSS), a special type of quantum statistical speed, has been recently introduced for low-dimensional quantum systems. Such a non-Markovianity witness is particularly useful, being easily computable since no diagonalization of the system density matrix is required. We investigate the sensitivity of this HSS-based witness to detect non-Markovianity in various high-dimensional and multipartite open quantum systems with finite Hilbert spaces. We find that the time behaviors of the HSS-based witness are always in agreement with those of quantum negativity or quantum correlation measure. These results show that the HSS-based witness is a faithful identifier of the memory effects appearing in the quantum evolution of a high-dimensional system with a finite Hilbert space. 相似文献
129.
Maura Pellei Carlo Santini Giancarlo Gioia Lobbia Franco Cantalamessa Cinzia Nasuti Mariacristina Di Prinzio Rosita Gabbianelli Giancarlo Falcioni 《应用有机金属化学》2005,19(5):583-589
New organotin(IV) derivatives containing the anionic ligands bis(3,5‐dimethylpyrazol‐1‐yl)dithioacetate [LCS2]− and bis(3,5‐dimethylpyrazol‐1‐yl)acetate [LCO2]− have been synthesized from reaction between (CH3)2SnCl2 and lithium salts of the ligands. Mononuclear complexes of the type {[LCX2](CH3)2SnCl} (X = S or O) have been obtained and fully characterized by elemental analyses and FT‐IR in the solid state and by NMR (1H, 13C and 119Sn) spectroscopy, conductivity measurements and electrospray ionization mass spectrometry in solution. The acute toxicity of new organotin(IV) derivatives on rat was studied, comparing their effect with those of dimethyltin chloride (CH3)2SnCl2. The comparison of LD50 of organotin(IV) complexes and (CH3)2SnCl2 administered intraperitoneally, as a single dose, evaluated in vivo on rats, showed that toxicity decreases as follows: (CH3)2SnCl2 > LCO2 > LCS2. The effect of these organotin(IV) complexes on DNA was evaluated in vitro and in vivo on rats treated with different doses of these compounds (1/20 LD50 and 1/100 LD50). The lymphocyte DNA status was assessed by the comet assay, a rapid and sensitive single‐cell electrophoresis technique, used to detect primary DNA damage in individual cells. After 36 h from the start of treatment the two new organotin(IV) derivatives induced a significant rise in comet assay parameters, indicating an increasing presence of damaged DNA. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
130.
Fulvio Ratto Paolo Matteini Alberto Cini Sonia Centi Francesca Rossi Franco Fusi Roberto Pini 《Journal of nanoparticle research》2011,13(9):4337-4348
We investigate the photothermal conversion and transformation of gold nanoparticles with an initial dogbone shape after dispersion
in hydrated chitosan films, which is a representative model of biological tissue, and excitation by a CW diode laser for 1 min.
Gold nanodogbones are observed to undergo a distinct modification above a sharp threshold of ~11 W cm−2 and 110 °C. Surprisingly, the very same modification is achieved up to at least 36 W cm−2 and 250 °C. We use an analytical model derived from Gans theory to associate the change in color of the films with the change
in shape statistics of these gold nanoparticles. This model proves both convenient and dependable. We interpret the photothermal
transformation as a rearrangement of particles with a dogbone shape and an aspect ratio of 4.1 into rods with an aspect ratio
of 2.5, where material from the end lobes of the dogbones may relocate to the waists of the rods. In turn, additional transitions
to stable gold nanospheres may exhibit fairly slower kinetics. 相似文献