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101.
Sara N. Pratt Daniel E. Austin 《Journal of the American Society for Mass Spectrometry》2014,25(5):712-721
The survivability of Bacillus subtilis spores and vegetative Escherichia coli cells after electrospray from aqueous suspension was tested using mobility experiments at atmospheric pressure. E. coli did not survive electrospray charging and desolvation, but B. subtilis did. Experimental conditions ensured that any surviving bacteria were de-agglomerated, desolvated, and electrically charged. Based on mobility measurements, B. subtilis spores survived even with 2,000–20,000 positive charges. B. subtilis was also found to survive introduction into vacuum after either positive or negative electrospray. Attempts to measure the charge distribution of viable B. subtilis spores using electrostatic deflection in vacuum were inconclusive; however, viable spores with low charge states (less than 42 positive or less than 26 negative charges) were observed. Graphical Abstract
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102.
Dr. Sachin Handa Daniel J. Lippincott Donald H. Aue Prof. Bruce H. Lipshutz 《Angewandte Chemie (International ed. in English)》2014,53(40):10658-10662
Asymmetric gold‐catalyzed hydrocarboxylations are reported that show broad substrate scope. The hydrophobic effect associated with in situ‐formed aqueous nanomicelles gives good to excellent ee’s of product lactones. In‐flask product isolation, along with the recycling of the catalyst and the reaction medium, are combined to arrive at an especially environmentally friendly process. 相似文献
103.
Dr. S. James Ratnakar Dr. Sara Chirayil Dr. Alexander M. Funk Dr. Shanrong Zhang Prof. João F. Queiró Prof. Carlos F. G. C. Geraldes Prof. Zoltan Kovacs Prof. A. Dean Sherry 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(48):21855-21860
Paramagnetic chemical exchange saturation transfer (paraCEST) agents are well-suited for imaging tissue pH because the basis of CEST, chemical exchange, is inherently sensitive to pH. Several previous pH-sensitive paraCEST agents were based on an exchanging Ln3+-bound water molecule as the CEST antenna but this design often added additional line-broadening to the bulk water signal due to T2 exchange. We report herein a pH-sensitive paraCEST agent that lacks an inner-sphere water molecule but contains one Ln-bound −OH group for CEST activation. The Yb3+ complex, Yb( 1 ), displayed a single, highly shifted CEST peak originating from the exchangeable Yb-OH proton, the frequency of which changed over the biologically relevant pH range. CEST images of phantoms ranging in pH from 6 to 8 demonstrate the potential of this agent for imaging pH. Initial rodent imaging studies showed that Gd( 1 ) remains in the vascular system much longer than anticipated but is cleared slowly via renal filtration. 相似文献
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Saurav Goel Sara Hawi Gaurav Goel Vijay Kumar Thakur Anupam Agrawal Clare Hoskins Oliver Pearce Tanvir Hussain Hari M. Upadhyaya Graham Cross Asa H. Barber 《Materials Today Chemistry》2020
The world is witnessing tumultuous times as major economic powers including the US, UK, Russia, India, and most of Europe continue to be in a state of lockdown. The worst-hit sectors due to this lockdown are sales, production (manufacturing), transport (aerospace and automotive) and tourism. Lockdowns became necessary as a preventive measure to avoid the spread of the contagious and infectious “Coronavirus Disease 2019” (COVID-19). This newly identified disease is caused by a new strain of the virus being referred to as Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS CoV-2; formerly called 2019-nCoV). We review the current medical and manufacturing response to COVID-19, including advances in instrumentation, sensing, use of lasers, fumigation chambers and development of novel tools such as lab-on-the-chip using combinatorial additive and subtractive manufacturing techniques and use of molecular modelling and molecular docking in drug and vaccine discovery. We also offer perspectives on future considerations on climate change, outsourced versus indigenous manufacturing, automation, and antimicrobial resistance. Overall, this paper attempts to identify key areas where manufacturing can be employed to address societal challenges such as COVID-19. 相似文献
106.
David A. Burns Eric M. Press M. A. Siegler Rebekka S. Klausen V. Sara Thoi 《Angewandte Chemie (International ed. in English)》2020,59(2):763-768
We report the synthesis of a set of 2D metal–organic frameworks (MOFs) constructed with organosilicon‐based linkers. These oligosilyl MOFs feature linear SinMe2n(C6H4CO2H)2 ligands (lin‐Sin, n=2, 4) connected by Cu paddlewheels. The stacking arrangement of the 2D sheets is dictated by van der Waals interactions and is tunable by solvent exchange, leading to reversible structural transformations between many crystalline and amorphous phases. 相似文献
107.
Curulli Antonella Montesperelli Giampiero Ronca Sara Cavalagli Nicola Ubertini Filippo Padeletti Giuseppina Vecchio Ciprioti Stefano 《Journal of Thermal Analysis and Calorimetry》2020,142(5):1721-1737
Journal of Thermal Analysis and Calorimetry - In the frame of the HERACLES (HEritage Resilience Against CLimate Events on Site) project, a set of cultural heritage sites was studied to improve... 相似文献
108.
Daouda Ndiaye Maryame Sy Agns Pallier Sandra Même Isidro de Silva Sara Lacerda Aline M. Nonat Loïc J. Charbonnire va Tth 《Angewandte Chemie (International ed. in English)》2020,59(29):11958-11963
The search for more biocompatible alternatives to Gd3+‐based MRI agents, and the interest in 52Mn for PET imaging call for ligands that form inert Mn2+ chelates. Given the labile nature of Mn2+, high inertness is challenging to achieve. The strongly preorganized structure of the 2,4‐pyridyl‐disubstituted bispidol ligand L1 endows its Mn2+ complex with exceptional kinetic inertness. Indeed, MnL1 did not show any dissociation for 140 days in the presence of 50 equiv. of Zn2+ (37 °C, pH 6), while recently reported potential MRI agents MnPyC3A and MnPC2A‐EA have dissociation half‐lives of 0.285 h and 54.4 h under similar conditions. In addition, the relaxivity of MnL1 (4.28 mm ?1 s?1 at 25 °C, 20 MHz) is remarkable for a monohydrated, small Mn2+ chelate. In vivo MRI experiments in mice and determination of the tissue Mn content evidence rapid renal clearance of MnL1. Additionally, L1 could be radiolabeled with 52Mn and the complex revealed good stability in biological media. 相似文献
109.
Gilbert Mercieca Sara Odoardi Serena Mestria Marisa Cassar Sabina Strano‐Rossi 《Journal of separation science》2020,43(14):2858-2868
The constant emergence of new psychoactive substances is a challenge to clinical and forensic toxicologists who need to constantly update analytical techniques to detect them. A large portion of these substances are synthetic cannabinoids. The aim of this study was to develop a rapid and simple method for the determination of synthetic cannabinoids and their metabolites in urine and blood using gas chromatography–mass spectrometry. The method involves an ultrasound‐assisted dispersive liquid–liquid microextraction that implies a rapid procedure, giving excellent extraction efficiencies with minimal use of toxic solvents. This is followed by silylation and analysis with gas chromatography–mass spectrometry. The chromatographic method allows for the separation and identification of 29 selected synthetic cannabinoids and some metabolites. The method was validated on urine and blood samples with the ability to detect and quantify all analytes with satisfactory limits of detection (from 1 to 5 ng/mL), limits of quantification (5 ng/mL), and selectivity and linearity (in the range of 5–200 ng/mL). The developed assay is highly applicable to laboratories with limited instrumental availability, due to the use of efficient and low‐cost sample preparation and instrumental equipment. The latter may contribute to enhance the detection of new psychoactive substances in clinical and forensic toxicology laboratories. 相似文献
110.