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
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
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
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
Compared with paclitaxel,sirolimus has been more used in the treatment of vascular restenosis gradually as an anti-proliferative drug,but few basic studies have elucidated its mechanism.The anti-proliferative effects ...Compared with paclitaxel,sirolimus has been more used in the treatment of vascular restenosis gradually as an anti-proliferative drug,but few basic studies have elucidated its mechanism.The anti-proliferative effects of sirolimus or paclitaxel have been demonstrated by numerous studies under normoxia,but few studies have been achieved focusing hypoxia.In this study,porcine carotid artery injury model and classical cobalt chloride hypoxia cell model were established.Sirolimus nanoparticles(SRM-NPs),paclitaxel nanoparticles(PTX-NPs)and blank nanoparticles(Blank-NPs)were prepared respectively.The effect of RPM-NPs on the degree of stenosis,proliferative index and the expression of PCNA after 28 days of porcine carotid artery injury model was evaluated.Compared with saline group and SRM groups,SRM-NPs group suppressed vascular stenosis,proliferative index and the expression of PCNA(P<0.01 and P<0.05).Endothelial cell(EC)and smooth muscle cell(SMC)were pre-treated with cobaltous chloride,followed by SRM-NPs,PTX-NPs,Blank-NPs or PBS control treating,the effects on cell proliferation,HIF-1 expression and glycolysis were detected.SRM-NPs could inhibit EC and SMC proliferation under hypoxia,while PTX-NPs couldn't(P<0.001).Significant differences between sirolimus and paclitaxel NPs in anti-proliferation effect under normoxia and hypoxia may due to the different inhibitory effects on HIF-1αexpression and glycolysis.In conclusion,these results suggest that sirolimus can inhibit the proliferation of hypoxic cells more effectively than paclitaxel.These observations may provide a basis for understanding clinical vascular stenosis therapeutic differences between rapamycin and paclitaxel.展开更多
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
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
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
OBJECTIVE:To investigate anti-endotoxin action of four OAs reacted with endotoxin by the LAL assay with KTA.METHODS:Using a incubating kinetic tube reader and kinetic turbidimetric assay(KTA),the concentration-respons...OBJECTIVE:To investigate anti-endotoxin action of four OAs reacted with endotoxin by the LAL assay with KTA.METHODS:Using a incubating kinetic tube reader and kinetic turbidimetric assay(KTA),the concentration-response time curve of endotoxin reacted with limulus amebocyte lysate(LAL) at 37℃ were obtained and the action of four organic acids(OAs) on it were investigated.The four OAs were benzoic acid,salicylic acid,syringic acid and 2-amino-benzoic acid from Radix isatidis.Meanwhile,the temperature variation caused by endotoxin with the four OAs was studied by the rabbit pyrogen test(RPT).RESULTS:It was showed that a low concentration(1 mg/mL) of the four OAs had a little effect of anti-endotoxin,and when the concentrations of the four OAs were 30 mg/mL,the endotoxin was neutralized completely.The relationships between the concentrations of endotoxin and the OAs were all linear with correlation coefficients of greater than 0.9995,indicating that the four OAs all had strong anti-endotoxin action,while syringic acid had the strongest action among the four OAs with IC50 of 12.84 mg/mL.CONCLUSION:The investigations of KTA agreed well with the results obtained by means of RPT.展开更多
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
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
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
Background:Though many countries,including China,are moving towards malaria elimination,malaria remains a major global health threat.Due to the spread of antimalarial drug resistance and the need for innovative medica...Background:Though many countries,including China,are moving towards malaria elimination,malaria remains a major global health threat.Due to the spread of antimalarial drug resistance and the need for innovative medical products during the elimination phase,further research and development(R&D)of innovative tools in both epidemic and elimination areas is needed.This study aims to identify the trends and gaps in malaria R&D in China,and aims to offer suggestions on how China can be more effectively involved in global malaria R&D.Methods:Quantitative analysis was carried out by collecting data on Chinese malaria-related research programmes between 1985 and 2014,invention patents in China from 1985 to 2014,and articles published by Chinese researchers in PubMed and Chinese databases from 2005 to 2014.All data were screened and extracted for numerical analysis and were categorized into basic sciences,drug/drug resistance,immunology/vaccines,or diagnostics/detection for chronological and subgroup comparisons.Results:The number of malaria R&D activities have shown a trend of increase during the past 30 years,however these activities have fluctuated within the past few years.During the past 10 years,R&D on drug/drug resistance accounted for the highest percentages of research programmes(32.4%),articles(55.0%in PubMed and 50.6%in Chinese databases)and patents(45.5%).However,these R&D activities were mainly related to artemisinin.R&D on immunology/vaccines has been a continuous interest for China’s public entities,but the focus remains on basic science.R&D in the area of high-efficiency diagnostics has been rarely seen or reported in China.Conclusions:China has long been devoted to malaria R&D in multiple areas,including drugs,drug resistance,immunology and vaccines.R&D on diagnostics has received significantly less attention,however,it should also be an area where China can make a contribution.More focus on malaria R&D is needed,especially in the area of diagnostics,if China would like to contribute in a more significant way to global malaria control and elimination.展开更多
文摘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.
基金Supported by the National Natural Science Foundation of China(21076015,21376018,21576014)the Fundamental Research Funds for the Central Universities(ZY1503)
文摘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.
基金supported by the National Natural Science Foundation of China(Grant Nos.91233111,61274041,and 11275228)the Special Funds for Major State Basic Research Project of China(Grant No.2012CB619305)+1 种基金the National High Technology R&D Program of China(Grant Nos.2014AA032603 and2014AA032609)the Guangdong Provincial Special Fund for LED Industrial Development,China(Grant No.2012A080302003)
文摘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.
基金Supported by the National Natural Science Foundation of China (No. 61073079)the Fundamental Research Funds for the Central Universities (2011JBM216,2011YJS021)
文摘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.
基金support from the National Natural Science Foundation of China of China(31771097)Tianjin Research Program of Application Foundation and Advanced Technology(17JCZDJC3070)+1 种基金AMS Innovation Fund for Medical Sciences(2017-I2M-1–016)Tianjin Innovation and Promotion Plan Key Innovation Team of Immunoreactive Biomaterials.
文摘Compared with paclitaxel,sirolimus has been more used in the treatment of vascular restenosis gradually as an anti-proliferative drug,but few basic studies have elucidated its mechanism.The anti-proliferative effects of sirolimus or paclitaxel have been demonstrated by numerous studies under normoxia,but few studies have been achieved focusing hypoxia.In this study,porcine carotid artery injury model and classical cobalt chloride hypoxia cell model were established.Sirolimus nanoparticles(SRM-NPs),paclitaxel nanoparticles(PTX-NPs)and blank nanoparticles(Blank-NPs)were prepared respectively.The effect of RPM-NPs on the degree of stenosis,proliferative index and the expression of PCNA after 28 days of porcine carotid artery injury model was evaluated.Compared with saline group and SRM groups,SRM-NPs group suppressed vascular stenosis,proliferative index and the expression of PCNA(P<0.01 and P<0.05).Endothelial cell(EC)and smooth muscle cell(SMC)were pre-treated with cobaltous chloride,followed by SRM-NPs,PTX-NPs,Blank-NPs or PBS control treating,the effects on cell proliferation,HIF-1 expression and glycolysis were detected.SRM-NPs could inhibit EC and SMC proliferation under hypoxia,while PTX-NPs couldn't(P<0.001).Significant differences between sirolimus and paclitaxel NPs in anti-proliferation effect under normoxia and hypoxia may due to the different inhibitory effects on HIF-1αexpression and glycolysis.In conclusion,these results suggest that sirolimus can inhibit the proliferation of hypoxic cells more effectively than paclitaxel.These observations may provide a basis for understanding clinical vascular stenosis therapeutic differences between rapamycin and paclitaxel.
基金supported by the National Natural Science Foundation of China under Grant No.61071077
文摘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.
基金Project supported by the National Basic Research Program of China (Grant No. 2006CB604904)the National Natural Science Foundation of China (Grant Nos. 60976057,61274072,and 60776037)
文摘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.
基金financially co-supported by the National Natural Science Foundation of China (U1404514)Henan Outstanding Person Foundation in China (144200510020)the Collaborative Innovation Center of Major Machine Manufacturing in Liaoning, China
文摘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.
基金support of Nova of Beijing science and Technology (No. 2010B108)National Natural Science Fond (No. 30701091)
文摘OBJECTIVE:To investigate anti-endotoxin action of four OAs reacted with endotoxin by the LAL assay with KTA.METHODS:Using a incubating kinetic tube reader and kinetic turbidimetric assay(KTA),the concentration-response time curve of endotoxin reacted with limulus amebocyte lysate(LAL) at 37℃ were obtained and the action of four organic acids(OAs) on it were investigated.The four OAs were benzoic acid,salicylic acid,syringic acid and 2-amino-benzoic acid from Radix isatidis.Meanwhile,the temperature variation caused by endotoxin with the four OAs was studied by the rabbit pyrogen test(RPT).RESULTS:It was showed that a low concentration(1 mg/mL) of the four OAs had a little effect of anti-endotoxin,and when the concentrations of the four OAs were 30 mg/mL,the endotoxin was neutralized completely.The relationships between the concentrations of endotoxin and the OAs were all linear with correlation coefficients of greater than 0.9995,indicating that the four OAs all had strong anti-endotoxin action,while syringic acid had the strongest action among the four OAs with IC50 of 12.84 mg/mL.CONCLUSION:The investigations of KTA agreed well with the results obtained by means of RPT.
文摘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.
基金The authors thank the National Key Basic Research Program of China,the National Natural Science Foundation of China (Nos.91027041 and 20920102033) for financial support,and Key Laboratory of Photochemical Conversion and Optoelectronic Materials,TIPC,CAS for financial support
文摘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.
文摘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.
基金supported by the Beijing Higher Education Young Elite Teacher Project(No.YETP0560)the Fundamental Research Funds for the Central Universities(No.2014JBZ012)the Beijing Jiaotong University Young Scholar Research Funding,China(No.2013RC017)
基金This research was supported by China UK Global Health Support Programme funded by UK DFID(grant no.GHSP-CS-OP301)China Postdoctoral Science Foundation(grant no.2014 M560027)National Natural Science Foundation of China(grant no.71503015)。
文摘Background:Though many countries,including China,are moving towards malaria elimination,malaria remains a major global health threat.Due to the spread of antimalarial drug resistance and the need for innovative medical products during the elimination phase,further research and development(R&D)of innovative tools in both epidemic and elimination areas is needed.This study aims to identify the trends and gaps in malaria R&D in China,and aims to offer suggestions on how China can be more effectively involved in global malaria R&D.Methods:Quantitative analysis was carried out by collecting data on Chinese malaria-related research programmes between 1985 and 2014,invention patents in China from 1985 to 2014,and articles published by Chinese researchers in PubMed and Chinese databases from 2005 to 2014.All data were screened and extracted for numerical analysis and were categorized into basic sciences,drug/drug resistance,immunology/vaccines,or diagnostics/detection for chronological and subgroup comparisons.Results:The number of malaria R&D activities have shown a trend of increase during the past 30 years,however these activities have fluctuated within the past few years.During the past 10 years,R&D on drug/drug resistance accounted for the highest percentages of research programmes(32.4%),articles(55.0%in PubMed and 50.6%in Chinese databases)and patents(45.5%).However,these R&D activities were mainly related to artemisinin.R&D on immunology/vaccines has been a continuous interest for China’s public entities,but the focus remains on basic science.R&D in the area of high-efficiency diagnostics has been rarely seen or reported in China.Conclusions:China has long been devoted to malaria R&D in multiple areas,including drugs,drug resistance,immunology and vaccines.R&D on diagnostics has received significantly less attention,however,it should also be an area where China can make a contribution.More focus on malaria R&D is needed,especially in the area of diagnostics,if China would like to contribute in a more significant way to global malaria control and elimination.