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Nanotechnology in Refractory Patent Applications 被引量:1
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作者 SHI Wei ZHENG Kai +2 位作者 GAO Zhichun ZHOU Wen ZHONG Weibing 《China's Refractories》 CAS 2016年第3期36-41,共6页
Nanotechnology is one of the most important hightech in the 21 st century. The application of nanotechnology to refractory industry is fruitful. It has created many advanced products,and produced a large amount of pat... Nanotechnology is one of the most important hightech in the 21 st century. The application of nanotechnology to refractory industry is fruitful. It has created many advanced products,and produced a large amount of patents. In this paper,we analyze the nanotechnology in refractory patent applications to find out the technology development trends. It will help the domestic enterprises to learn the state of global patent applications in refractory industry,promote their technologies,and create better products. 展开更多
关键词 NANOTECHNOLOGY REFRACTORY patent appli-cations
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Effect of the thickness of InGaN interlayer on a-plane GaN epilayer
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作者 王建霞 汪连山 +6 位作者 张谦 孟祥岳 杨少延 赵桂娟 李辉杰 魏鸿源 王占国 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第2期357-361,共5页
In this paper,we use the a-plane InGaN interlayer to improve the property of a-plane GaN.Based on the a-InGaN interlayer,a template exhibits that a regular,porous structure,which acts as a compliant effect,can be obta... In this paper,we use the a-plane InGaN interlayer to improve the property of a-plane GaN.Based on the a-InGaN interlayer,a template exhibits that a regular,porous structure,which acts as a compliant effect,can be obtained to release the strain caused by the lattice and thermal mismatch between a-GaN and r-sapphire.We find that the thickness of InGaN has a great influence on the growth of a-GaN.The surface morphology and crystalline quality both are first improved and then deteriorated with increasing the thickness of the InGaN interlayer.When the InGaN thickness exceeds a critical point,the a-GaN epilayer peels off in the process of cooling down to room temperature.This is an attractive way of lifting off a-GaN films from the sapphire substrate. 展开更多
关键词 non-polar a-plane GaN InGaN interlayer peel-off metalorganic chemical vapor deposition
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Interpreting the dynamic effect of internal heat integration on reactive distillation columns
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作者 Yang Yuan Liang Zhang +3 位作者 Haisheng Chen Shaofeng Wang Kejin Huang Huan Shao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第1期89-102,共14页
In this work,the impact of internal heat integration upon process dynamics and controllability by superposing reactive section onto stripping section,relocating feed locations,and redistributing catalyst within the re... In this work,the impact of internal heat integration upon process dynamics and controllability by superposing reactive section onto stripping section,relocating feed locations,and redistributing catalyst within the reactive section is explored based on a hypothetical ideal reactive distillation system containing an exothermic reaction:A + BC + D.Steady state operation analysis and closed-loop controllability evaluation are carried out by comparing the process designs with and without the consideration of internal heat integration.For superposing reactive section onto stripping section,favorable effect is aroused due to its low sensitivities to the changes in operating condition.For ascending the lower feed stage,somewhat detrimental effect occurs because of the accompanied adverse internal heat integration and strong sensitivity to the changes in operating condition.For descending the upper feed stage,serious detrimental effect happens because of the introduced adverse internal heat integration and strong sensitivity to the changes in operating condition.For redistributing catalyst in the reactive section,fairly small negative influence is aroused by the sensitivity to the changes in operating condition.When reinforcing internal heat integration with a combinatorial use of these three strategies,the decent of the upper feed stage should be avoided in process development.Although the conclusions are derived based on the hypothetical ideal reactive distillation column studied,they are considered to be of general significance to the design and operation of other reactive distillation columns. 展开更多
关键词 Reactive distillation column Internal heat integration Process design Process dynamics Process control
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Patent Protection in Daily Chemical Industry in China
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作者 Shengju Deng Wei Yin +1 位作者 Yongfu Sun Jun Pei 《China Detergent & Cosmetics》 2016年第2期37-42,共6页
In this paper, the present patent situation of the daily chemical industry was analyzed. The development trends of China patent protection in daily chemical industry were analyzed including patent application trend, p... In this paper, the present patent situation of the daily chemical industry was analyzed. The development trends of China patent protection in daily chemical industry were analyzed including patent application trend, patent type and applicant type. As a leading enterprise, the patent protection situation of P&G was analyzed, which is significant for domestic enterprises. Finally, suggestions for China daily chemical industry were given according to the analysis results and experiences of the leading company from the perspective of patent protection. 展开更多
关键词 daily chemical industry COSMETICS patent protection
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Simultaneous Determination of 2- and 3-MCPD Esters in Infant Formula Milk Powder and Edible Vegetable Oils by Gas Chromatography-Mass Spectrometry
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作者 Huan Yao Siqi Zeng +2 位作者 Xianghua Wang Hang Li Bing Du 《American Journal of Analytical Chemistry》 2023年第10期421-433,共13页
Esters of 2- and 3-monochloropropane-1,2-diol (MCPD) are significative contaminants of processed edible oils used as foods or food ingredients. The aim of this study was to develop and validate a new method by GC-MS f... Esters of 2- and 3-monochloropropane-1,2-diol (MCPD) are significative contaminants of processed edible oils used as foods or food ingredients. The aim of this study was to develop and validate a new method by GC-MS for the simultaneous quantification of 2 and 3-MCPD esters in infant milk powder and edible vegetable oils. The developed protocol included fat fraction in infant milk powder and edible vegetable oils samples was extracted and treated with sodium methylate-methanol to cleave the ester bonds of the 2- and 3-MCPD esters, moreover, standard samples of deuterium isotope-labeled 2- and 3-MCPD palmitic acid double esters and stearic acid double esters were used as the internal standards. Furthermore, this method was validated when it was applied to food products, concrete manifestation in its good accuracy (the recovery of MCPD esters ranged from 86% to 114%), high sensitivity (the LOD of 3-MCPD and 2-MCPD esters were 0.025 and 0.020 mg/kg, LOQ were 0.075, 0.060 mg/kg, respectively) and satisfactory repeatability (RSD below 6.8%) for all analytes. In the 150 commercial edible vegetable oils and infant formula milk powder samples, we obtained a preliminary profile of MCPD ester contamination. 展开更多
关键词 3-MCPD 2-MCPD GC-MS Infant Milk Powder Edible Vegetable Oils
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Distribution of contact loads in crushed zone between tunnel boring machine disc cutter and rock 被引量:11
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作者 SHI Yu-peng XIA Yi-min +2 位作者 TAN Qing ZHANG Yi-chao QIAO Shuo 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第9期2393-2403,共11页
The construction efficiency and quality of tunnel boring machines(TBMs)is largely determined by the service life of cutting tools,which is the result of contact loads in the crushed zone between cutter ring and rock.I... The construction efficiency and quality of tunnel boring machines(TBMs)is largely determined by the service life of cutting tools,which is the result of contact loads in the crushed zone between cutter ring and rock.In this paper,a series of rock breaking tests were conducted with a 216 mm diameter disc cutter and concrete samples.Based on the superposition principle,the distribution of contact loads between disc cutter and rock were obtained by using the truncated singular value decomposition(TSVD).The results show that both the peak value and the whole numerical distribution of the radial strains on the cutter ring increase with the increase of the penetration.The distribution curves of the contact loads show an approximate parabola going downwards,which indicates contact loads are more concentrated.The front non-loading area with a ratio from 1.8%to 5.4%shows an increasing trend with the increase of penetration.However,the change of rear non-loading area is not obvious.It is believed that the conclusions have guidance for the study of rock breaking mechanism and manufacturing process of the disc cutter. 展开更多
关键词 disc cutter contact loads superposition principle non-loading area
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Temperature-resistant and salt-tolerant mixed surfactant system for EOR in the Tahe Oilfield 被引量:3
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作者 Ji-Xiang Guo Shi-Ling Zhang +4 位作者 Yu-Qi Yang Zi-Jing Yu Liang Li Yu-Shan Wang Long-Sheng Zhang 《Petroleum Science》 SCIE CAS CSCD 2021年第2期667-678,共12页
A new temperature-resistant and salt-tolerant mixed surfactant system(referred to as the SS system)for enhancing oil recovery at the Tahe Oilfield(Xinjiang,China)was evaluated.Based on the analysis of the crude oil,th... A new temperature-resistant and salt-tolerant mixed surfactant system(referred to as the SS system)for enhancing oil recovery at the Tahe Oilfield(Xinjiang,China)was evaluated.Based on the analysis of the crude oil,the formation water and rock components in the Tahe Oilfield,the long-term thermal stability,salt tolerance and the ability to change the wettability,interfacial activity and oil washing efficiency of the mixed surfactant system were studied.The system contains the anionic surfactant SDB and another cationic surfactant SDY.When the total mass concentration of the SS solution is 0.15 wt%,m(SDB)/m(SDY)ratio is 1 to 1,and excellent efficiencies are achieved for oil washing for five kinds of Tahe Oilfield crude oils(more than 60%).In addition,after adding cationic surfactant,the adsorption capacity of the surfactant is further reduced,reaching 0.261 mg/g.The oil displacement experiments indicate that under a temperature of 150°C and a salinity of 24.6×104 mg/L,the SS system enhances the oil recovery by over 10%after water flooding.The SS anionic–cationic surfactant system is first presented in the open literature that can be successfully applied to obtain predictions of Tahe Oilfield carbonate reservoirs with a high temperature and high salinity. 展开更多
关键词 Mixed surfactant system Temperature resistance Salt tolerance Carbonate reservoir Enhanced oil recovery
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Comparative Analysis of Mobile Application Stores in Different Charging Modes
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作者 沈孟如 周正 +1 位作者 董宝田 张晋豫 《China Communications》 SCIE CSCD 2013年第12期158-168,共11页
This paper describes the platformisation of the mobile services domain,which in recent years has become a successful strategy for some hardware manufacturers and software companies.While having different platform stra... This paper describes the platformisation of the mobile services domain,which in recent years has become a successful strategy for some hardware manufacturers and software companies.While having different platform strategies and business models,they have succeeded in creating a demand for mobile software and content with end-users.This paper proposes a way to determine the optimum platform-charging mode that an operator should adopt to play a meaningful role in the mobile service domain and with respect to content with end-users.Four charging modes employed by mobile application stores are studied in this paper,namely the one-sided paid-by-users charging mode,the one-sided paid-by-advertisers charging mode,the two-sided differential paid charging mode and the two-sided paid and free access charging mode.Furthermore,a comparative analysis of the four modes is also presented. 展开更多
关键词 mobile application store two-si-ded platform charging mode
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Patent eligibility of software inventions
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作者 Du Heng 《China Intellectual Property》 2021年第4期88-94,共7页
Article 25 of the Patent Law provides for six types of subject matters for which no patent right should be granted.No matter how practical,novel or inventive they are,specific results covered by such subject matters a... Article 25 of the Patent Law provides for six types of subject matters for which no patent right should be granted.No matter how practical,novel or inventive they are,specific results covered by such subject matters are excluded from patent protection.Nevertheless,the determination of ineligible subject matters does not require evidence to aid comparison as in the case of commenting on novelty or inventiveness,which can be concluded directly and merely by deductive reasoning.Therefore,it is particularly important to clearly define the concept of the various statutory exclusions in the article. 展开更多
关键词 PATENT protection. PATENT
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AN IMPROVED SPARSITY ADAPTIVE MATCHING PURSUIT ALGORITHM FOR COMPRESSIVE SENSING BASED ON REGULARIZED BACKTRACKING 被引量:3
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作者 Zhao Ruizhen Ren Xiaoxin +1 位作者 Han Xuelian Hu Shaohai 《Journal of Electronics(China)》 2012年第6期580-584,共5页
Sparsity Adaptive Matching Pursuit (SAMP) algorithm is a widely used reconstruction algorithm for compressive sensing in the case that the sparsity is unknown. In order to match the sparsity more accurately, we presen... Sparsity Adaptive Matching Pursuit (SAMP) algorithm is a widely used reconstruction algorithm for compressive sensing in the case that the sparsity is unknown. In order to match the sparsity more accurately, we presented an improved SAMP algorithm based on Regularized Backtracking (SAMP-RB). By adapting a regularized backtracking step to SAMP algorithm in each iteration stage, the proposed algorithm can flexibly remove the inappropriate atoms. The experimental results show that SAMP-RB reconstruction algorithm greatly improves SAMP algorithm both in reconstruction quality and computational time. It has better reconstruction efficiency than most of the available matching pursuit algorithms. 展开更多
关键词 Compressive sensing Reconstruction algorithm Sparsity adaptive Regularized back-tracking
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First identification of isatin-β-thiosemicarbazones as novel inhibitors of New Delhi metallo-β-lactamase-1: Chemical synthesis, biological evaluation and molecular simulation 被引量:2
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作者 Guo-Qing Song Wei-Min Wang +2 位作者 Zai-Shun Li Ying Wang Jian-Guo Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第6期899-902,共4页
New Delhi metallo-b-lactmase-1(NDM-1) catalyzes the hydrolysis of b-lactam antibiotics and cleaves the b-lactam ring of the molecule, conferring bacterial resistance against these medicines. In an effort to discover... New Delhi metallo-b-lactmase-1(NDM-1) catalyzes the hydrolysis of b-lactam antibiotics and cleaves the b-lactam ring of the molecule, conferring bacterial resistance against these medicines. In an effort to discover novel agents to treat this superbug, an old drug methisazone was found to be a weak NDM-1 inhibitor, with an IC50 of 297.6 mmol/L. Based on this result, a series of isatin-β-thiosemicarbazones(IBTs)were synthesized and biologically evaluated as novel NDM-1 inhibitors. Nine of the IBT compounds showed IC50 values of 〈10 mmol/L, the best of which was 2.72 mmol/L. Comparative field analysis(Co MFA) contour maps were generated to depict the structural features and molecular docking was performed to understand the possible binding mode of these inhibitors. The present research hereby has provided valuable information for further discovery of NDM-1 inhibitors. 展开更多
关键词 New Delhi metallo-β-lactmase-1 Isatin-β-thiosemicarbazones In vitro enzyme inhibition Molecular docking
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Design, Synthesis and Insecticidal Evaluation of Novel N-Pyridylpyrazolecarboxamide Derivatives Containing Isoxazole, Isoxazoline and 1,3,4-Thiadiazole Rings 被引量:2
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作者 HUA Xuewen LIU Chen +4 位作者 ZHOU Sha CHEN Minggui XIONG Lixia LI Yongqiang LI Zhengming 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2017年第6期882-889,共8页
With the introduction of various heterocyclic rings at the benzene part of anthranilic diamides, a series of N-pylidylpyrazolecarboxamide derivatives containing isoxazole, isoxazoline and 1,3,4-thiadiazole rings was d... With the introduction of various heterocyclic rings at the benzene part of anthranilic diamides, a series of N-pylidylpyrazolecarboxamide derivatives containing isoxazole, isoxazoline and 1,3,4-thiadiazole rings was designed, synthesized and evaluated for their insecticidal activities. The structures of the obtained novel target compounds were confirmed by means of 1H NMR, 13C NMR and HRMS. The bioassay results indicated that most of the target compounds displayed moderate or good insecticidal activities against oriental armyworm and diamondback moth at the adopted concentrations compared with chlorantraniliprole, especially compounds Ii andII , of which the LC50 and LC95 values against oriental armyworm were further measured. The structure-activity relationship demonstrated that the introduction of chlorine in benzene ring, bromomethyl and acetoxyl substituents in 4,5-dihydroisoxazole part was more advantageous to improve the corresponding insecticidal activities than the introduction of other substitnents and heterocycles. 展开更多
关键词 Diamide insecticide N-Pyridylpyrazolecarboxamide Insecticidal activity
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Broadband light emitting from multilayer-stacked InAs/GaAs quantum dots
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作者 刘宁 金鹏 王占国 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期408-411,共4页
We report the effect of the GaAs spacer layer thickness on the photoluminescence (PL) spectral bandwidth of InAs/GaAs self-assembled quantum dots (QDs). A PL spectral bandwidth of 158 nm is achieved with a five-la... We report the effect of the GaAs spacer layer thickness on the photoluminescence (PL) spectral bandwidth of InAs/GaAs self-assembled quantum dots (QDs). A PL spectral bandwidth of 158 nm is achieved with a five-layer stack of InAs QDs which has a 11-nm thick GaAs spacer layer. We investigate the optical and the structurM properties of the multilayer-stacked InAs/GaAs QDs with different GaAs spacer layer thicknesses. The results show that the spacer thickness is a key parameter affecting the multi-stacked InAs/GaAs QDs for wide-spectrum emission. 展开更多
关键词 quantum dots broudband spectrum superluminescent diode
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Cage slip characteristics of a cylindrical roller bearing with a trilobe-raceway 被引量:9
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作者 Sier DENG Yujia LU +2 位作者 Wenhu ZHANG Xue SUN Zhenwei LU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第2期351-362,共12页
Based on dynamic analysis of rolling bearings, the nonlinear dynamic differential equations of a cylindrical roller bearing with a trilobe-raceway were established and solved by the GSTIFF(gear stiff) integer algori... Based on dynamic analysis of rolling bearings, the nonlinear dynamic differential equations of a cylindrical roller bearing with a trilobe-raceway were established and solved by the GSTIFF(gear stiff) integer algorithm with a variable step. The influences of structural parameters and the tolerance of the trilobe-raceway, working conditions of the bearing, and the outer ring installation method on cage slip characteristics were investigated. The results show that:(i) The cage slip ratio and bearing rating life of a cylindrical roller bearing with a trilobe-raceway would reduce when the low-radius(radius of the outer raceway contour at the lowest point) and D-value(difference value between the high and low points of the outer raceway contour) decrease, and the former(low-radius) contributes more significantly.(ii) The cage slip ratio of a cylindrical roller bearing with a trilobe-raceway rises with the increase of the bearing speed, and decreases with the increase of the radial force; the variation range increases with the increase of the low-radius.(iii) When the installation angle of the outer ring increases in a period, the cage slip ratio remains unchanged while the bearing rating life rises up a little. Therefore, when installing a cylindrical roller bearing with a trilobe-raceway, the location of the maximum radius shall be under that of the radial force to improve the bearing rating life.(iv) With the increase of the roundness of the base circle where the radius of the lowest points of the trilobe-raceway contour locates, the cage slip ratio rises gradually and the bearing rating life decreases. 展开更多
关键词 Bearing rating life Cage slip ratio DYNAMICS Raceway contour Trilobe-raceway
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Ti incorporation in MCM-41 mesoporous molecular sieves using hydrothermal synthesis 被引量:1
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作者 Shengping WANG Changqing MA +1 位作者 Yun SHI Xinbin MA 《Frontiers of Chemical Science and Engineering》 SCIE EI CAS CSCD 2014年第1期95-103,共9页
Abstract Titanium-containing mesoporous materials (Ti-MCM-41) were obtained by hydrothennal synthesis. Such materials are active catalysts for the transesterifica- tion of dimethyl oxalate and phenol to produce diph... Abstract Titanium-containing mesoporous materials (Ti-MCM-41) were obtained by hydrothennal synthesis. Such materials are active catalysts for the transesterifica- tion of dimethyl oxalate and phenol to produce diphenyl oxalate. To understand the role of the Ti in the catalytic process, Ti-MCM-41 samples with different Si/Ti ratios (from 5 to 100) were prepared and the samples were analyzed by Fourier transform infrared spectroscopy, UV- visible spectroscopy, and ammonia temperature pro- grammed desorption. It was concluded that the Ti is incorporated into the framework of the MCM-41 and formed weak Lewis acid sites. In addition, the number of Ti(IV) sites increased as the amount of titanium increased. X-ray powder diffraction, N2 adsorpfion-desorption and transmission electron microscopy results showed that the Ti-MCM-41 samples have a hexagonal arrangement of mono-dimensional pores. A large number of Ti(IV) sites coupled with the mesoporous structure and large pore diameters are favorable for the transesterification catalytic properties of Ti-MCM-41. 展开更多
关键词 TI-MCM-41 mesoporous molecular sieve acid sites TRANSESTERIFICATION hydrothermal synthesis
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Synthesis, Insecticidal Activities and Molecular Docking Studies on cis-Nitenpyram Analogues with a Flexible Amido Segment Anchored on Tetrahydropyrimidine Ring 被引量:1
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作者 FANG Ting SUN Chuanwen +3 位作者 XU Yiyi YUAN Jing WANG Yuanfeng XING Jiahua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2014年第6期931-936,共6页
To make further studies on the difference of cis-nitenpyram analogues, a series of cis-nitenpyram com- pounds containing a flexible amido segment anchored on tetrahydropyrimidine ring was designed and synthesized. Pre... To make further studies on the difference of cis-nitenpyram analogues, a series of cis-nitenpyram com- pounds containing a flexible amido segment anchored on tetrahydropyrimidine ring was designed and synthesized. Preliminary bioassays indicate that all the analogues exhibit a mortality of 100% at 100 rag/L, and the analogue 4d shows the best activity against Nilaparvata lugens and Myzus persicae, with a mortality of 100% at 4 mg/L (LCs0=0.172 rag/L). The structure activity relationship studies show that insecticidal activities of the analogues are affected by the kinds and size of substituent R. In addition, the molecular docking simulations reveal that compouds 4 with a flexible amido segment on tetrahydropyrimidine ring show their different binding affinities for the nicotinic acetyleholine receptor(nAChR) of insect and compoud 4d shows stronger hydrogen-bonding with nAChR, which may provide the structure-activity relationship observed in vitro. 展开更多
关键词 cis-Nitenpyram analogue Nicotinic acetylcholine receptor(nAChR) Flexible amido segment Hydro-gen-bonding action Structure activity relationship Insecticidal activity Molecular docking
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A correction method of color projection fringes in 3D contour measurement 被引量:4
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作者 宋丽梅 李宗艳 +3 位作者 陈昌曼 习江涛 郭庆华 李晓捷 《Optoelectronics Letters》 EI 2015年第4期303-306,共4页
In the three-dimensional(3D) contour measurement,the phase shift profilometry(PSP) method is the most widely used one.However,the measurement speed of PSP is very low because of the multiple projections.In order to im... In the three-dimensional(3D) contour measurement,the phase shift profilometry(PSP) method is the most widely used one.However,the measurement speed of PSP is very low because of the multiple projections.In order to improve the measurement speed,color grating stripes are used for measurement in this paper.During the measurement,only one color sinusoidal fringe is projected on the measured object.Therefore,the measurement speed is greatly improved.Since there is coupling or interference phenomenon between the adjacent color grating stripes,a color correction method is used to improve the measurement results.A method for correcting nonlinear error of measurement system is proposed in this paper,and the sinusoidal property of acquired image after correction is better than that before correction.Experimental results show that with these correction methods,the measurement errors can be reduced.Therefore,it can support a good foundation for the high-precision 3D reconstruction. 展开更多
关键词 correction contour projection grating correcting projected pixel sinusoidal fringe Tianjin
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Stereoselective Photochemical Reaction of Cyclohexyl Phenyl Ketone within Lytropic Liquid Crystals Formed by Chiral Ionic Liquids
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作者 Xiujie Yang Xinwei Li +4 位作者 Bin Chen Lizhu Wu Liping Zhang Liqiang Zheng Chenho Tung 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2013年第5期603-606,共4页
Irradiation of cyclohexyl phenyl ketone (1) results in either intra- or intermolecular hydrogen abstraction to af- ford compounds 1-phenylhept-6-en-l-one (2) and a-cyclohexyl benzyl alcohol (3) as photoproducts,... Irradiation of cyclohexyl phenyl ketone (1) results in either intra- or intermolecular hydrogen abstraction to af- ford compounds 1-phenylhept-6-en-l-one (2) and a-cyclohexyl benzyl alcohol (3) as photoproducts, in which 3 has a pair of enantiomers. Herein, two types of chiral hexagonal liquid crystals were prepared to direct the enantioselec- tive photochemical reaction of 1. One of the hexagonal liquid crystals is composed of 1-tetradecyl-3-methyl- imidazolium bromide/p-xylene/H2O with the modification by a chiral inductor. The other one is formed by chiral (S)-3-hexadecyl-1-(1-hydroxy-propan-2-yl)-imidazolium bromide/p-xylene/H2O. The product analysis shows that the latter one can be used as a microreactor to achieve stereoselective photochemical reaction, while the former one produced compound 3 with no enantioselectivity at all. 展开更多
关键词 ENANTIOSELECTIVITY chiral ionic liquid liquid crystal MICROREACTOR
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Classification of Tomicus Species
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作者 Li Xia Zhang Zhen +2 位作者 Cao Peng Wang Hongbin Han Pingding 《Chinese Forestry Science and Technology》 2012年第3期45-45,共1页
Both morphological characters and a portion of of 28S rDNA sequences were used to identifying Tomicus species.The specimens were classed into groups with the following characters: 1) granules or punctures on interstri... Both morphological characters and a portion of of 28S rDNA sequences were used to identifying Tomicus species.The specimens were classed into groups with the following characters: 1) granules or punctures on interstria 2 on the declivity of the elytra;2) length of the elytral interstrial hairs and hairs arising from punctures;3) arrangement of pronotal punctures and hairs.These characters could be clearly examined under a binocular microscope at 30×magnification and they were applicable and valuable for the forest entomologists to identify Tomicus species.The phylogenetic tree established with difference in 28S rDNA sequence of D2 region revealed that the specimens of each group identified by morphological characters were also grouped together.The genetic distances of intra-species, inter-species and inter-genus were not overlapped. Genetic divergence of 28S rDNA was also useful for identifying Tomicus species. 展开更多
关键词 Tomicus MORPHOLOGY KEY to SPECIES of Tomicus 28S RDNA
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Canopy structure:An intermediate factor regulating grassland diversity-function relationships under human disturbances 被引量:1
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作者 Xiaoxia Zhao Yuhao Feng +9 位作者 Kexin Xu Mengqi Cao Shuya Hu Qiuli Yang Xiaoqiang Liu Qin Ma Tianyu Hu Maggi Kelly Qinghua Guo Yanjun Su 《Fundamental Research》 CAS CSCD 2023年第2期179-187,共9页
Grasslands are one of the largest coupled human-nature terrestrial ecosystems on Earth,and severe anthropogenic-induced grassland ecosystem function declines have been reported recently.Understanding factors influenci... Grasslands are one of the largest coupled human-nature terrestrial ecosystems on Earth,and severe anthropogenic-induced grassland ecosystem function declines have been reported recently.Understanding factors influencing grassland ecosystem functions is critical for making sustainable management policies.Canopy structure is an important factor influencing plant growth through mediating within-canopy microclimate(e.g.,light,water,and wind),and it is found coordinating tightly with plant species diversity to influence forest ecosystem functions.However,the role of canopy structure in regulating grassland ecosystem functions along with plant species diversity has been rarely investigated.Here,we investigated this problem by collecting field data from 170 field plots distributed along an over 2000 km transect across the northern agro-pastoral ecotone of China.Aboveground net primary productivity(ANPP)and resilience,two indicators of grassland ecosystem functions,were measured from field data and satellite remote sensing data.Terrestrial laser scanning data were collected to measure canopy structure(represented by mean height and canopy cover).Our results showed that plant species diversity was positively correlated to canopy structural traits,and negatively correlated to human activity intensity.Canopy structure was a significant indicator for ANPP and resilience,but their correlations were inconsistent under different human activity intensity levels.Compared to plant species diversity,canopy structural traits were better indicators for grassland ecosystem functions,especially for ANPP.Through structure equation modeling analyses,we found that plant species diversity did not have a direct influence on ANPP under human disturbances.Instead,it had a strong indirect effect on ANPP by altering canopy structural traits.As to resilience,plant species diversity had both a direct positive contribution and an indirect contribution through mediating canopy cover.This study highlights that canopy structure is an important intermediate factor regulating grassland diversity-function relationships under human disturbances,which should be included in future grassland monitoring and management. 展开更多
关键词 Grassland ecosystem function Canopy structure Plant species diversity Human activity intensity Northern agro-pastoral ecotone
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