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61.
Xiao Hui SU Gang LI Rui Sen LIN Eiichi KIKUCHI Masahiko MATSUKATA 《中国化学快报》2006,17(7):977-980
Zeolite membrane is an important category of inorganic membranes with many advantages such as thermal and chemical stability, high mechanical strength as well as the unique pore structure of molecular dimension. Up to now, many types of zeolite including … 相似文献
62.
Nakayama T Kurosawa Y Furui S Kerman K Kobayashi M Rao SR Yonezawa Y Nakano K Hino A Yamamura S Takamura Y Tamiya E 《Analytical and bioanalytical chemistry》2006,386(5):1327-1333
Polymerase chain reaction (PCR) is an essential part of research based on genomics or cell analysis. The development of a
microfluidic device that would be suitable for high-temperature-based reactions therefore becomes an important contribution
towards the integration of micro-total analysis systems (μTAS). However, problems associated with the generation of air bubbles
in the microchannels before the introduction of the assay liquid, which we call the “initial start-up” in this study, made
the flow irregular and unstable. In this report, we have tried to address these problems by adapting a novel liquid-flow method
for high-temperature-based reactions. A PDMS-based microfluidic device was fabricated by soft-lithography techniques and placed
on a cartridge heater. The generation of the air bubbles was prevented by introducing the fluorinated oil, an inert and highly
viscous liquid, as the cap just before the introduction of the sample solutions into the microchannels. The technique was
applied for continuous-flow PCR, which could perform PCR on-chip in a microfluidic system. For the evaluation of practical
accuracy, plasmid DNA that serves as a reference molecule for the quantification of genetically modified (GM) maize was used
as the template DNA for continuous-flow PCR. After PCR, the products were collected in a vial and analyzed by gel electrophoresis
to confirm the accuracy of the results. Additionally, quantitative continuous-flow PCR was performed using TaqMan technology
on our PCR device. A laser detection system was also used for the quantitative PCR method. We observed a linear relationship
between the threshold cycle (Ct) and the initial DNA concentration. These results showed that it would be possible to quantify
the initial copies of the template DNA on our microfluidic device. Accurate quantitative DNA analysis in microfluidic systems
is required for the integration of PCR with μTAS, thus we anticipate that our device would have promising potential for applications
in a wide range of research. 相似文献
63.
The sensor for adenosine-5′-triphosphate (ATP) is based on H+-ATPase immobilized via a polyvinylbutyral resin on a pH-sensitive field effect transistor. A linear relationship was obtained between the initial rate of change of the differential gate output voltage and the logarithm of the ATP concentration over the range 0.2–1.0 mM ATP. The optimum pH was 9.0 at 40°C but pH 7.0 was preferred for routine measurements. Only slight responses were obtained for 1 mM glucose, creatinine or urea. The ATP-sensing system exhibited a response to 1 mM ATP for at least 18 days. 相似文献
64.
Dianions of dimetallic hexa(organo)[70]fullerene [(C5R5)2Ru2C70Ar6]2? (R=H, Me; Ar=Ph, 4‐MeC6H4, 4‐tBuC6H4) react with benzylic bromide to yield the dibenzylated product dimetallic octa(organo)[70]fullerene (C5R5)2Ru2C70Ar6(CH2Ar′)2 (Ar′=Ph, 4‐MeO2CC6H4), where the benzylic groups are attached to the equatorial belt region of [70]fullerene; this region is generally considered to be rather unreactive. This unusual structure was unambiguously determined by X‐ray crystallography. Theoretical studies on the electronic properties of the monoanionic intermediate indicated that the highest spin density resides on the two carbon atoms in the belt region; one of them then couples with a benzylic radical to yield the octa(organo)fullerene product after ionic substitution of the fullerene anion with a benzylic bromide. Electrochemical analysis of the hexa(organo) and octa(organo) ruthenium complexes suggests that the modification of the belt region does not affect the electronic communication between the two metal centers. 相似文献
65.
Laurean Ilies Dr. Yoshiharu Sato Dr. Chikahiko Mitsui Hayato Tsuji Dr. Eiichi Nakamura Prof. Dr. 《化学:亚洲杂志》2010,5(6):1376-1381
A diversity‐oriented synthetic strategy allowed us to design a series of conjugated molecules containing multiple benzosilole units that can be utilized as efficient hole‐blocking materials for phosphorescent organic light emitting diodes (OLEDs). Some of these compounds showed a performance surpassing that of the current standard, bathocuproine. The new compounds were easily synthesized in a modular fashion from a previously reported 3‐stannyl benzosilole building unit. Studies on the properties of these compounds in solution and in the solid state indicate that they possess high electron affinity, high ionization potential, and form stable amorphous films that show high electron‐drift mobility. The correlation between their molecular properties and the efficiency of the OLED device performance is also investigated. 相似文献
66.
The concept of relative t-designs for Q-polynomial association schemes is due to Delsarte (Philips Res Rep 32:373–411, 1997). We formulate Fisher type lower bounds as well as the concept of tight relative 2- and 4-designs very explicitly for binary Hamming association schemes H(n, 2). Then we discuss some examples of tight relative 2- and 4-designs on H(n, 2) in this sense, in connection with the work of Woodall (Proc Lond Math Soc (3) 20:669–687, 1970), Enomoto-Ito-Noda (Osaka J Math 16:39–43, 1979), and others. The present paper is expected to be the first of a series of our studies of tight relative t-designs on Q-polynomial association schemes in a more general context. 相似文献
67.
68.
Phase transition of the layer structure of poly(p-benzenedithiol-co-p-diethylbenzene) obtained in solid state polymerization was studied by a thermal treatment or UV irradiation under a nitrogen atmosphere. The peak intensities in the X-ray diffraction diagram of polymers gradually decreased with the thermal treatment time above 55°C. Below 50°C the layer structure of polymers hardly changed. The apparent activation energy for the phase transition was about 15 Kcal/mol [63 KJ/mol] at the initial stage and gradually decreased to a few Kcal/mol [ca. 2 KJ/mol]. UV light from a high-pressure mercury lamp also gradually induced the phase transition from the layer structure to an amorphous one. The pristine polymer possesses phase transition points at 75, 95 and 130°C. The exothermic transition at 75°C can be understood as the thermal destruction of the semistable layer structure. The exothermic transition at 95°C may be correspond to the cis → trans thermal isomerization of the C?°C bond in the polymer main chain. The diffuse reflectance spectrum of the pristine polymer differed from that of the amorphous polymer obtained by the thermal treatment of the pristine polymer. SEM photographs of the pristine polymer showed a particular surface structure, i.e. entangled fibrous material. TEM photographs of the pristine polymer exhibited a bright valley-and-hill structure, whereas that of the amorphous polymer obtained by thermal treatment exhibited a plain surface. 相似文献
69.
A variety of polysubstituted 1H-indenes can be prepared through the copper-catalyzed arylative cyclization of simple arylalkynes with commercially available aromatic sulfonyl chlorides that function as an aryl group donor. The reaction tolerates a broad range of functional groups, including bromide and iodide, nitrile, ketone, and nitro groups. The reaction allowed the synthesis of polycyclic aromatic hydrocarbons, such as a bis(indene), indacene, and fused polyarene derivatives, some of them showing strong fluorescence in solution and the solid state. 相似文献
70.
Eiichi Masumoto Hiroshi Maruoka Fumi Okabe Sho Nishida Yuki Yoshimura Toshihiro Fujioka Kenji Yamagata 《Journal of heterocyclic chemistry》2011,48(1):96-104
Dihydropyridazinones 4a , 4b , N‐substituted dihydropyrazoles 5b , 5c , 5d , and O‐substituted pyrazoles 6a , 6b , 6c , 6d have been synthesized starting from spirocyclopropanepyrazole derivative 2 . Treatment of 2 with α‐chloro esters, e.g., methyl chloroacetate, ethyl chloroacetate, isopropyl chloroacetate, and tert‐butyl chloroacetate, in potassium carbonate/sodium iodide system caused ring opening and subsequent C‐ or N‐attack nucleophilic substitution to give the corresponding dihydropyridazinones 4a , 4b and N‐substituted dihydropyrazoles 5b , 5c , 5d . On the other hand, in the absence of sodium iodide, O‐substituted pyrazoles 6a , 6b , 6c , 6d were obtained from 2 via an O‐attack nucleophilic substitution. J. Heterocyclic Chem., 2011. 相似文献