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71.
Preparation and certification of hijiki reference material, NMIJ CRM 7405-a, from the edible marine algae hijiki (Hizikia fusiforme) 总被引:1,自引:0,他引:1
Narukawa T Inagaki K Zhu Y Kuroiwa T Narushima I Chiba K Hioki A 《Analytical and bioanalytical chemistry》2012,402(4):1713-1722
A certified reference material, NMIJ CRM 7405-a, for the determination of trace elements and As(V) in algae was developed
from the edible marine hijiki (Hizikia fusiforme) and certified by the National Metrology Institute of Japan (NMIJ), the National Institute of Advanced Industrial Science
and Technology (AIST). Hijiki was collected from the Pacific coast in the Kanto area of Japan, and was washed, dried, powdered,
and homogenized. The hijiki powder was placed in 400 bottles (ca. 20 g each). The concentrations of 18 trace elements and
As(V) were determined by two to four independent analytical techniques, including (ID)ICP-(HR)MS, ICP-OES, GFAAS, and HPLC-ICP-MS
using calibration solutions prepared from the elemental standard solution of Japan calibration service system (JCSS) and the
NMIJ CRM As(V) solution, and whose concentrations are certified and SI traceable. The uncertainties of all the measurements
and preparation procedures were evaluated. The values of 18 trace elements and As(V) in the CRM were certified with uncertainty
(k = 2). 相似文献
72.
Kitagawa Y Mori Y Komeda O Ishii K Hanayama R Fujita K Okihara S Sekine T Satoh N Kurita T Takagi M Kawashima T Kan H Nakamura N Kondo T Fujine M Azuma H Motohiro T Hioki T Nishimura Y Sunahara A Sentoku Y 《Physical review letters》2012,108(15):155001
A compact fast core heating experiment is described. A 4-J 0.4-ns output of a laser-diode-pumped high-repetition laser HAMA is divided into four beams, two of which counterilluminate double-deuterated polystyrene foils separated by 100 μm for implosion. The remaining two beams, compressed to 110 fs for fast heating, illuminate the same paths. Hot electrons produced by the heating pulses heat the imploded core, emitting x-ray radiations >20 eV and yielding some 10(3) thermal neutrons. 相似文献
73.
74.
Nakagawa H Ogawa K Satake A Kobuke Y 《Chemical communications (Cambridge, England)》2006,(14):1560-1562
A supramolecular triad consisting of self-assembled imidazolyl-zinc-porphyrin dimer, ferrocene, and fullerene was successfully constructed, resulting in long-lived charge separated species after efficient photoinduced electron transfer and charge shift reactions. 相似文献
75.
Kubo M Nishimoto R Doi M Kodama M Hioki H 《Chemical communications (Cambridge, England)》2006,(32):3390-3392
We developed a new labeling reagent and a color assay system in water to detect binding between target molecules and library members on beads, which is free of label-induced artifacts that can cause misleading results. 相似文献
76.
Amidosulfuric acid and sodium carbonate as standards for acid–base titrimetry were assayed by coulometric titration and gravimetric
titration. Amidosulfuric acid was directly assayed by coulometric titration with electrogenerated hydroxide ions, and sodium
carbonate was assayed by gravimetric back-titration. For sodium carbonate, excess amount of sulfuric acid, whose concentration
was determined by coulometric titration, was added to sodium carbonate, and then gravimetrically back-titrated using a sodium
hydroxide solution whose concentration was determined by gravimetric titration using the sulfuric acid. The accuracy of the
coulometric titration for amidosulfuric acid and sulfuric acid was evaluated by examining the current efficiency of pulse
electrolysis, the amount of the electrolysis current used, and the time spent for a titration. In addition, the drying conditions
for high purity primary standards have a significant effect on the titration results due to changes in the acid–base assay.
The suitable drying conditions for amidosulfuric acid and sodium carbonate were evaluated by mass-change measurements, coulometric
titration and gravimetric titration. The measurement uncertainties were estimated from the uncertainties on the titration
processes. Finally, the assays of amidosulfuric acid and sodium carbonate were 99.986% ± 0.010% (k = 2) after drying at 50 °C for 2 h, and 99.970% ± 0.016% (k = 2) after drying at 280 °C for 4 h, respectively. In addition, the international consistency was confirmed by measuring
certified reference materials (CRMs) available from different National Metrology Institutes, and the compatibility of values
among CRMs was experimentally ascertained. 相似文献
77.
David L. Duewer Kenneth W. Pratt Chainarong Cherdchu Nongluck Tangpaisarnkul Akiharu Hioki Masaki Ohata Petra Spitzer Michal Máriássy Leoš Vyskočil 《Accreditation and quality assurance》2014,19(5):329-342
The key comparison (KC) studies of the Consultative Committee for Amount of Substance—Metrology in Chemistry help ensure the reliability of chemical and biochemical measurements relevant to international trade and environmental-, health-, and safety-related decision making. The traditional final evaluation of each measurement result reported by a KC participant is a “degree of equivalence” (DEq) that quantitatively specifies how consistent each individual result is relative to a reference value. Recognizing the impossibility of conducting separate KCs for all important analytes in all important sample matrices at all important analyte levels, emphasis is now shifting to documenting broadly applicable critical or “core” measurement competencies elicited through a series of studies. To better accomplish the necessary synthesis of results, data analysis and display tools must be developed for objectively and quantitatively combining individual DEqs. The information detailed in the 11 KCs of primary method pH measurements publically available as of 2013 provides an excellent “best case” prototype for such analysis. We here propose tools that enable documenting the expected primary pH measurement performance of individual participants between pH 1 and pH 11 and from 15 °C to 37 °C. These tools may prove useful for other areas where the uncertainty of measurement is a predictable function of the measured quantity, such as the stable gases. That results for relatively simple measurement processes can be combined using relatively simple analysis and display methods does not ensure that similarly meaningful summaries can be devised for less well understood and controlled systems, but it provides the incentive to attempt to do so. 相似文献
78.
Akira Hasegawa Yuichi Hioki Etzuko Yamamoto Makoto Kiso Ichiro Azuma 《Journal of carbohydrate chemistry》2013,32(3):359-369
A variety of N-[2-O-(2-acetamido-6-O-acyl-1-S-acyl-2, 3-dideoxy-1-thio-β3-D-glucocyranose-3-yl)-D-lactoyl]-L-alanyl-D-isoglutamine methyl esters were synthesized. Their immunoadjuvant activities were examined in guinea-pigs. 相似文献
79.
Yusaku Hioki Hiroki Kuyama Chikako Hamana Kohei Takeyama Koichi Tanaka 《Journal of mass spectrometry : JMS》2013,48(11):1217-1223
We describe here an optimization study of the sample preparation conditions for sensitive detection of peptides by matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS). Among many factors in the conditions, we varied the percent acetonitrile in the peptide solution, the percent acetonitrile in the matrix solution and the α‐cyano‐4‐hydroxycinnamic acid (CHCA) concentration in the matrix solution. CHCA was chosen because it is the most frequently used matrix for analyzing peptides. The well‐established dried‐droplet method was employed for sample deposition. The examined range of the concentration of CHCA was from 0.01 to 10 mg/ml, and the MeCN content of the solvent for matrix/analyte was 10% to 50%. The indicator for the detection sensitivity was the S/N ratio of the peaks of peptides used. Highly increased sensitivity (100‐ to 1000‐fold) was observed for the optimal CHCA concentration of 0.1 mg/ml in 20% MeCN/0.1% aq. trifluoroacetic acid (TFA), as compared with the conventional concentration (10 mg/ml) in 50% MeCN/0.1% aq. TFA. For example, the limit of detection of human ACTH 18–39 was 10 amol/well for the optimal condition but 10 fmol/well for the conventional condition. The optimal condition (0.1 mg/ml CHCA in 20% MeCN/0.1% aq. TFA) was verified with five model peptides and provided significant improvement in sensitivity (by two to three orders of magnitude) compared with the conventional conditions. Optimizing the CHCA concentration and solvent composition significantly improved the detection sensitivity in the analysis of peptides by MALDI‐MS. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
80.
A single crystal of sapphire was implanted with 100-keV57Fe to a dose of 3.4×1015 ions/cm2. The charge states of iron ions were investigated with the CEMS technique at low temperatures. The formation of the observed
charge states Fe2+(1) and Fe2+(2) were elucidated in terms of crystal structure. 相似文献