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961.
Two dibenzo[Def,Mno]chrysene‐based polymeric semiconductors: Surprisingly opposite device performances in field‐effect transistors and solar cells
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Jisu Hong Yebyeol Kim Song Bong Lee Soon‐Ki Kwon Yun‐Hi Kim Chan Eon Park 《Journal of polymer science. Part A, Polymer chemistry》2016,54(16):2559-2570
A new series of conjugated polymers containing dibenzo[def, mno]chrysene units were successfully designed and synthesized to investigate their physical properties and device performances in field‐effect transistors and photovoltaic cells. Two polymers, namely poly(4,10‐bithiophene‐6,12‐bis(2‐decyltetradecyloxy)‐dibezo[def, mno]chrysene) ( PTTC) and poly(2,2′‐thiophenevinylenthiophene‐4,10‐[6,12‐bis(2‐decyltetradecyloxy)‐dibenzo[def, mno]chrysene]) ( PTVTC) , exhibited similar light absorption, electrochemical characteristics, and theoretical electronic structures. However, they behaved very differently when used in thin‐film transistors and solar cells. The PTTC polymer with two thiophene groups had better charge transport behavior, whereas the PTVTC polymer with two thiophene units connected by a vinyl group exhibited higher efficiency in bulk heterojunction photovoltaic cells. These results were discussed in terms of their nanostructural bulk morphologies established from transmission electron microscopy and two‐dimensional grazing incidence wide angle X‐ray scattering analyses. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2559–2570 相似文献
962.
Dr. Georgios Rotas Prof. Dr. Nikos Tagmatarchis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1206-1214
Energy conversion schemes have attracted considerable attention in recent years. A large amount of research effort has focused on fullerenes, particularly C60 and its derivatives, as suitable electron acceptors, owing to their outstanding properties. In this context, C59N‐based donor–acceptor systems have lately attracted attention, owing to their exceptional energy‐and electron‐transfer properties. As a result, chemical derivatization of C59N plays an important role in the realization of the aforementioned systems. The current Minireview aims to familiarize researchers with the main aspects of azafullerene synthesis, chemistry, and photophysical properties, while it mainly focuses on the synthetic methodologies employed for as well as on energy conversion schemes of azafullerene‐based donor–acceptor systems. 相似文献
963.
Diazaisoindigo bithiophene and terthiophene copolymers for application in field‐effect transistors and solar cells
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Wan Yue Cheng Li Xuelin Tian Weiwei Li Marios Neophytou Hu Chen Weiyuan Du Cameron Jellett Hung‐Yang Chen Ada Onwubiko Iain McCulloch 《Journal of polymer science. Part A, Polymer chemistry》2017,55(16):2691-2699
Two donor–acceptor conjugated polymers with azaisoindigo as acceptor units and bithiophene and terthiophene as donor units have been synthesized by Stille polymerization. These two polymers have been successfully applied in field‐effect transistors and polymer solar cells. By changing the donor component of the conjugated polymer backbone from bithiophene to terthiophene, the density of thiophene in the backbone is increased, manifesting as a decrease in both ionization potential and in electron affinity. Therefore, the charge transport in field‐effect transistors switches from ambipolar to predominantly hole transport behavior. PAIIDTT exhibits hole mobility up to 0.40 cm2/Vs and electron mobility of 0.02 cm2/Vs, whereas PAIIDTTT exhibits hole mobility of 0.62 cm2/Vs. Polymer solar cells were fabricated based on these two polymers as donors with PC61BM and PC71BM as acceptor where PAIIDTT shows a modest efficiency of 2.57% with a very low energy loss of 0.55 eV, while PAIIDTTT shows a higher efficiency of 6.16% with a higher energy loss of 0.74 eV. Our results suggest that azaisoindgo is a useful building block for the development of efficient polymer solar cells with further improvement possibility by tuning the alternative units on the polymer backbone. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2691–2699 相似文献
964.
TiO2 Nanobelts Decorated with In2S3 Nanoparticles as Photocatalysts with Enhanced Full‐Solar‐Spectrum (UV–vis–NIR) Photocatalytic Activity toward the Degradation of Tetracycline
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Yujie Li Tong Li Jian Tian Xinzhen Wang Hongzhi Cui 《Particle & Particle Systems Characterization》2017,34(7)
Herein, ultradispersed In2S3 nanoparticle (NP)/TiO2 nanobelt (NB) heterostructures with an intimate interfacial coupling effect are synthesized from the consideration of combining the visible/near‐infrared photoabsorption property of In2S3 with the excellent UV photocatalytic property of TiO2. In this process, the 1D TiO2 NBs not only perform as the support to form the heterostructure, but are also employed as a dispersant to confine the aggregation of In2S3 NPs. As expected, the obtained In2S3 NP/TiO2 NB heterostructure gives rise to a prominently strong optical absorption in the full solar region of 300–1800 nm, and thus displays a desired photocatalytic degradation of tetracycline in full utilization of all solar energy, compared with that of pristine In2S3 and TiO2. Besides, the In2S3 NP/TiO2 NB heterostructure photocatalysts have no selectivity and can effectively degrade other different kinds of organic pollutants, including cationic dyes (methyl blue and rhodamine B) and colorless chemical pollutants (phenol and salicylic acid). The exceptional photocatalytic enhancement is due to the synergistic interactions of heterojunction with the strong interfacial coupling effect, the In2S3 extended light absorption, efficient photogenerated e?/h+ pair separation, and fully exposed reactive sites induced by uniform packing of the ultrasmall In2S3. 相似文献
965.
Anamika Mishra Sonal Gupta Asit Patra 《Journal of polymer science. Part A, Polymer chemistry》2022,60(6):975-984
Direct C H arylation coupling reaction has gained significant importance in synthesis of conjugated polymers for organic electronic applications. We report here a facile and straightforward method called “direct C H arylation” reaction to synthesize conjugated 3,4-dioxythiophene and 1,4-dialkoxybenzene based copolymers as hole transport material (HTM) for perovskite solar cells. Two electron-rich conjugated polymers P1-2 were synthesized, in which 1,4-dibromo-2,5-bis(dodecyloxy)benzene and 3,4-dialkoxy-thiophene units were used for polymerization. The resulting polymers were characterized and exhibited high solubility in organic solvents. Electrochemical and optical characterizations were carried out by cyclic voltammetry and UV–Vis–NIR absorption spectroscopy and found that these polymers show higher-lying HOMO energy levels with wide band gap. Density functional theory calculation was performed on these polymers ( P1-2 ) and correlated with our experimental results. Finally, perovskite solar cells were fabricated by solution-processable deposition of P1-2 as dopant-free HTM with device geometry ITO/SnO2/Perovskite/HTM( P1 / P2 )/Ag and achieved a maximum power conversion efficiency of 5.28%. This study provides information on designing and simple preparation by direct C H arylation reaction of higher-lying HOMO energy level polymer as HTM for perovskite solar cells. 相似文献
966.
Qiuju Liang Zhangbo Hu Jianhong Yao Yukai Yin Puxin Wei Zhikang Chen Wangchang Li Jiangang Liu 《Journal of polymer science. Part A, Polymer chemistry》2022,60(6):917-944
Organic solar cells (OSCs) have unique advantages of low-cost solution processing, light weight, flexibility, and semitransparency, which is a promising photovoltaic technology. The intermixed phase plays a key role in determining the power conversion efficiencies (PCE) of OSCs. The intermixed phase is an amorphous region, where the donor and acceptor mix at the molecular level. Great efforts have been devoted to optimize the content and the composition of the intermixed phase. This perspective focuses on the functions of intermixed phase and elaborates the relationship between intermixed phase behavior and photophysical process, in particular, the exciton dissociation and charge transport. Then the characterization methods, including quantitative and qualitative characterizations, for the content and composition of intermixed phases are introduced. Meanwhile, this review also introduces the strategies to control the intermixed phase behavior, such as adjusting the miscibility between donor and acceptor, changing the ratio of donor to acceptor, regulating the crystallinity and so on. Moreover, representative examples are given and discussed to understand the key parameters on tuning the intermixed phase behavior. Finally, a future controlling and development of intermixed phase behavior is briefly outlooked, which may help to achieve high PCE of OSCs. 相似文献
967.
The impact of the work function of a metal back contact on lead methylammonium tri-iodide based perovskite solar cells without hole transport material (HTM) was analyzed using device simulation. The elimination of the HTM is attractive in terms of the simplification of device structure and fabrication process. In the solar cell, a back junction is formed by the perovskite absorber and metal back contact. The device simulation revealed that the elimination of the HTM did not change the built-in voltage (Vbi) of the device when the work function of the metal back contact (?M) was similar to the valence band maximum of the absorber (Ev_absorber). In the HTM-free structure, Vbi showed a high value if ?M was equal to or deeper than Ev_absorber. In contrast, when ?M was shallower than Ev_absorber, Vbi monotonically decreased, resulting in the decrease in open-circuit voltage of the device. The results showed the importance of the ?M matching to maintain Vbi, which is useful guideline for the design of the HTM-free perovskite solar cells. 相似文献
968.
《中国化学》2018,36(6):495-501
In this work, a new A‐D‐A type nonfullerene small molecular acceptor SiIDT‐IC, with a fused‐ring silaindacenodithiophene (SiIDT) as D unit and 2‐(3‐oxo‐2,3‐dihydroinden‐1‐ylidene)malononitrile (INCN) as the end A unit, was design and synthesized. The SiIDT‐IC film shows absorption peak and edge at 695 and 733 nm, respectively. The HOMO and LUMO of SiIDT‐IC are of −5.47 and −3.78 eV, respectively. Compared with carbon‐bridging, the Si‐bridging can result in an upper‐lying LUMO level of an acceptor, which is benefit to achieve a higher open‐circuit voltage in polymer solar cells (PSCs). Complementary absorption and suitable energy level alignment between SiIDT‐IC and wide bandgap polymer donor PBDB‐T were found. For the PBDB‐T:SiIDT‐IC based inverted PSCs, a D/A ratio of 1: 1 was optimal to achieve a power conversion efficiency (PCE) of 7.27%. With thermal annealing (TA) of the blend film, a higher PCE of 8.16% could be realized due to increasing of both short‐circuit current density and fill factor. After the TA treatment, hole and electron mobilities were elevated to 3.42 × 10−4 and 1.02 × 10−4 cm2·V−1·s−1, respectively. The results suggest that the SiIDT, a Si‐bridged fused ring, is a valuable D unit to construct efficient nonfullerene acceptors for PSCs. 相似文献
969.
970.
Haijun Fan Zhiguo Zhang Yongfang Li Xiaowei Zhan 《Journal of polymer science. Part A, Polymer chemistry》2011,49(6):1462-1470
Two copolymers of fluorene and thiophene with conjugated side‐chain pending acceptor end group of cyanoacetate ( P2 ) and malononitrile ( P3 ) were synthesized. Both polymers exhibit good thermal stability and low highest occupied molecular orbital level (?5.5 eV). In comparison with P2 , P3 exhibits stronger UV–vis absorption and higher hole mobility. Polymer solar cells based on P3 :PC71BM exhibits a power conversion efficiency of 1.33% under AM 1.5, 100 mW/cm2, which is three times of that based on P2 :PC71BM. The higher efficiency is attributed to better absorption, higher hole mobility, and the reduced phase separation scale in P3 :PC71BM blend. The aggregate domain size in P3 :PC71BM blend is 50 nm, much smaller than that in P2 :PC71BM blend (200 nm). Tiny difference in the end groups on side chains of P2 and P3 leads to great difference in phase separation scale, charge transport, and efficiency of their photovoltaic devices. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献