A nickel-catalyzed C(sp^(2))–H alkynylation of unprotected α-substituted benzylamines is achieved by utilizing a transient directing group. The combination of a TDG with a nickel catalyst significantly improves the ...A nickel-catalyzed C(sp^(2))–H alkynylation of unprotected α-substituted benzylamines is achieved by utilizing a transient directing group. The combination of a TDG with a nickel catalyst significantly improves the reaction step and atom economy. It has been investigated that the 2,4,6-trimethylpyridine ligand was critical to achieve the optimized reactivity. This protocol provides a straightforward route for synthesizing the alkynylated free benzylamines, featuring good substrate compatibility and monoselectivity.展开更多
The transition metal-catalyzed C–H activation have been considered as increasingly useful approach for installing new functional groups onto organic small molecules due to their high step-and atom-economy,the abundan...The transition metal-catalyzed C–H activation have been considered as increasingly useful approach for installing new functional groups onto organic small molecules due to their high step-and atom-economy,the abundance of hydrocarbon compounds,and the potential for late-stage functionalization of complex organic molecules.The ortho-and meta-C-H activation and functionalization of aromatic compounds have been widely explored in recent years,however the distal para-C-H activation and functionalization has remained a significant challenge because of the difficulty in forming energetically favorable metallacyclic transition states.The utilization of appropriate directing groups or templates as well as the meticulous design of catalysts and ligands has proven to be effective in transition-metal-catalyzed remote para-C-H bonds activation and functionalization of aromatic compounds.This review aims to summarize the strategies for controlling para-selective C–H functionalization using the directing group,template engineering,and catalyst/ligand design under transition metals catalysis in recent years.展开更多
The directing mechanisms of liquid directing agents of zeolite Y and zeolite L were studied by means of light transmission, ultracentrifugation, NMR, XRD and “cross-exchange” experiments. It was discovered that not ...The directing mechanisms of liquid directing agents of zeolite Y and zeolite L were studied by means of light transmission, ultracentrifugation, NMR, XRD and “cross-exchange” experiments. It was discovered that not only microcfystals of zeolites, but also cage structures of zeolites play the directing role for crystallization of zeolites.展开更多
In this work,we show for the first time that high-silica zeolites(MFI,TON,MTT,and*MRE)could be synthesized from a combined strategy of both zeolite seeding and alcohol filling in the absence of organic structure-direc...In this work,we show for the first time that high-silica zeolites(MFI,TON,MTT,and*MRE)could be synthesized from a combined strategy of both zeolite seeding and alcohol filling in the absence of organic structure-directing agents(OSDAs).High-silica ZSM-5 zeolites with Si/Al ratios ranging from 38 to 240(TF-Al-ZSM-5)could be synthesized via this route.The key to the success of this technique was the employment of an aluminosilicate precursor with a fully 4-coordinated aluminum species as the initial source,wherein the rearrangement and condensation of the silicate species,rather than the aluminate species,occurred during zeolite crystallization.In addition,heteroatoms,such as Fe and B,could be incorporated into the zeolite frameworks.Catalytic tests for the methanol-to-propylene(MTP)reaction exhibited good catalytic performance for TF-Al-ZSM-5,which was comparable to that of the aluminosilicate ZSM-5 zeolite synthesized with OSDAs.Hence,this method offers viable opportunities for the industrial production and catalytic application of high-silica zeolites in the future.展开更多
Zeolite synthesis in contemporary chemical industries is predominantly conducted using organic structure‐directing agents(OSDAs),which are chronically hazardous to humans and the environment.It is a growing trend to ...Zeolite synthesis in contemporary chemical industries is predominantly conducted using organic structure‐directing agents(OSDAs),which are chronically hazardous to humans and the environment.It is a growing trend to develop an eco‐friendly and nuisanceless OSDA for zeolite synthesis.Herein,choline is employed as a non‐toxic and green OSDA to synthesize high silica Y zeolite with SiO2/Al2O3 ratios of 6.5–6.8.The prepared Y zeolite samples exhibited outstanding(hydro)thermal stability at ultrahigh temperature owing to the higher SiO2/Al2O3 ratio.The XRF,SEM,29Si‐NMR and 13Na+results suggested that choline plays a structure‐directing role in the synthesis of Y zeolite,while the feed molar fraction of Na+is a crucial determinant for the framework SiO2/Al2O3 ratio and the crystal morphology.展开更多
Zeolite FAU composites with a macro/meso-microporous hierarchical structure were hydrothermally synthesized using macro-mesoporous γ-Al_2O_3 monolith as the substrate by means of the liquid crystallization directing...Zeolite FAU composites with a macro/meso-microporous hierarchical structure were hydrothermally synthesized using macro-mesoporous γ-Al_2O_3 monolith as the substrate by means of the liquid crystallization directing agent(LCDA) induced method. No template was needed throughout the synthesis processes. The structure and porosity of zeolite composites were analyzed by means of X-ray powder diffraction(XRD), scanning electron microscopy(SEM) and N_2adsorption-desorption isotherms. The results showed that the supported zeolite composites with varied zeolitic crystalline phases and different morphologies can be obtained by adjusting the crystallization parameters, such as the crystallization temperature, the composition and the alkalinity of the precursor solution. The presence of LCDA was defined as a determinant for synthesizing the zeolite composites. The mechanisms for formation of the hierarchically porous FAU zeolite composites in the LCDA induced synthesis process were discussed. The resulting monolithic zeolite with a trimodal-porous hierarchical structure shows potential applicability where facile diffusion is required.展开更多
Reported herein is the first example of heterogeneous palladium catalyzed C(sp^(3))-H bonds arylation by a transient-ligand-directed strategy.Using supported palladium(metallic state) na nopariticles as catalyst,a wid...Reported herein is the first example of heterogeneous palladium catalyzed C(sp^(3))-H bonds arylation by a transient-ligand-directed strategy.Using supported palladium(metallic state) na nopariticles as catalyst,a wide range of aryl iodides undergo the coupling with various o-methylbenzaldehyde derivatives to assemble a library of highly selective and functionalized o-benzylbenzaldehydes.The stability of the catalyst was easily recovered four runs without significant loss of activity.The XPS analysis of the catalyst before and after reaction indicated that the reaction might be carried out by a catalytic cycle starting with Pd~0.展开更多
Silicoaluminophosphates SAPO-11 molecular sieves with small particle size and hierarchical pores were synthesized using the directing agent method.The effect of crystallization time on the particle structure,morpholog...Silicoaluminophosphates SAPO-11 molecular sieves with small particle size and hierarchical pores were synthesized using the directing agent method.The effect of crystallization time on the particle structure,morphology,pore structure properties,and acid properties of SAPO-11 molecular sieves were investigated.Unlike the SAPO-11 molecular sieves synthesized with the conventional method,the results of XRD,SEM,BET and NH3-TPD analyses showed that the SAPO-11 molecular sieves synthesized by the directing agent method in a shorter crystallization time exhibited fine and uniform morphology.By increasing the crystallization time,the particle size of SAPO-11 molecular sieve was significantly reduced,and the mesoporous structure(intercrystalline pores)was formed.Furthermore,the external specific surface area and the total specific surface area reached 81.7 m^2/g and 192.0 m^2/g,respectively,which effectively reduced the pore mass transfer resistance and significantly increased the number of acid sites.The results of n-dodecane hydroisomerization revealed that the Pt/SAPO-11 prepared with the novel method exhibited higher catalytic activity and better hydroisomerization selectivity than that synthesized by the conventional hydrothermal method.Thus,the small particle molecular sieve showed a promising industrial application prospect to be used as catalyst support.展开更多
In this review, we highlight the recent development in Ru（II）-catalyzed C-H activations under redox neutral conditions. After a brief introduction of the C-H activations with oxidizing direct group by different tran...In this review, we highlight the recent development in Ru（II）-catalyzed C-H activations under redox neutral conditions. After a brief introduction of the C-H activations with oxidizing direct group by different transition metal catalysts, the examples with Ru（ll） catalyst were classified and introduced according to different internal oxidants used in the system. The features of each methodology will be highlighted and the plausible reaction mechanism will be presented if available.展开更多
Article 1 These regulations are formulated according to the rules of the State Law on foreign investment and the requirements of industrial policies to direct foreign investment, ensuring that it adapts to the program...Article 1 These regulations are formulated according to the rules of the State Law on foreign investment and the requirements of industrial policies to direct foreign investment, ensuring that it adapts to the programmes of China’s national economy and social development and protecting the legal rights and interests of investors.展开更多
Garlic planting requires a single seed with a scaly bud upward and vertically.In this study,an automatic garlic seed directing device was designed for auxiliary garlic seeding by utilizing a seed placed funnel,a corre...Garlic planting requires a single seed with a scaly bud upward and vertically.In this study,an automatic garlic seed directing device was designed for auxiliary garlic seeding by utilizing a seed placed funnel,a correcting mechanism,and an automatic control system.Three factors influenced device performance:characteristics of garlic seeds,limited notch diameter of the seed placed funnel,and funnel taper of the seed placed funnel.The most optimal structural parameters of the seed placed funnel were determined via theoretical analysis.The research samples of Lanling and Jinxiang garlic were divided into three groups according to their respective sizes.3D design software(Solidworks)was used to simulate the above three factors and analyze their rules of action.The obtained simulation results demonstrated that the suitable range of funnel taper and limited notch diameter of seed placed funnel for the three groups of seed were from 40°to 60°and 6-8 mm,respectively.The bench test showed that when the funnel taper was 60°and the limited notch diameter was 10 mm,the success rates of the three groups’seeds in terms of scaly bud directing were 89.8%,91.6%and 96.6%respectively,which satisfied the agricultural requirements of garlic planting.Accordingly,the corresponding results may promote the study and improvement of garlic intelligent planting equipment.展开更多
Transition-metal catalyzed C--H functionalization of benzaldehydes is of great interest in organic synthesis. Herein, we developed a transient directing group assisted amidation of benzaldehydes catalyzed by rhodium c...Transition-metal catalyzed C--H functionalization of benzaldehydes is of great interest in organic synthesis. Herein, we developed a transient directing group assisted amidation of benzaldehydes catalyzed by rhodium catalyst. With the employment of 10 mol% of 4-trifluoromethyl aniline, the in situ generated imine groups as the directing group efficiently enable this transformation. By using this protocol, a wide range of benzaldehydes were efficiently converted into the corresponding N-（2-formylphenyl）benzamides utilizing dioxazolones as the nitrogen source.展开更多
The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor ...The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion.展开更多
在相干信号波达方向(direction of arrival,DOA)估计中,当阵列接收到的相干信号处于低信噪比时,DOA估计性能会大大降低。针对该问题,提出一种增强的时空平滑(enhanced spatio-temporal smoothing,ESTS)算法,在使用时空相关矩阵重构接收...在相干信号波达方向(direction of arrival,DOA)估计中,当阵列接收到的相干信号处于低信噪比时,DOA估计性能会大大降低。针对该问题,提出一种增强的时空平滑(enhanced spatio-temporal smoothing,ESTS)算法,在使用时空相关矩阵重构接收数据矩阵的时空平滑(spatio-temporal smoothing,STS)方法的基础上进行了改进。首先对子阵列时空相关矩阵进行平方预处理,然后通过充分利用子阵列时空相关矩阵的协方差和互协方差信息解相干,提高了相干信号的分辨率以及对噪声扰动的鲁棒性。理论分析和统计结果均表明,与其他空间平滑类解相干方法相比,该方法提高了在低信噪比、少快拍数、小角度分离情况下的相干信号DOA估计的去相关性能。展开更多
In this paper we give the criteria and constructions of directing compo-nents of a representation-infinite algebra,and the structure of a trivial extension algebraT(A)having Z-component,where A is an iterated-tilted a...In this paper we give the criteria and constructions of directing compo-nents of a representation-infinite algebra,and the structure of a trivial extension algebraT(A)having Z-component,where A is an iterated-tilted algebra.展开更多
A strategy for Pd-catalyzed ortho-C–H silylation of biaryl aldehydes enabled by a transient auxiliary is presented. This protocol provides a broad range of ortho-silylated biaryl aldehydes in good yields. The silyl m...A strategy for Pd-catalyzed ortho-C–H silylation of biaryl aldehydes enabled by a transient auxiliary is presented. This protocol provides a broad range of ortho-silylated biaryl aldehydes in good yields. The silyl moiety can be further functionalized under mild conditions, rendering the silylated products useful building blocks. Notably, this protocol also offers an opportunity to establish a platform for expeditious synthesis of structurally diverse axially chiral biaryl aldehydes via sequential atroposelective interannular C–H functionalization/intraanular C–H silylation.展开更多
BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Resear...BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level.展开更多
Noninvasive brain stimulation techniques offer promising therapeutic and regenerative prospects in neurological diseases by modulating brain activity and improving cognitive and motor functions.Given the paucity of kn...Noninvasive brain stimulation techniques offer promising therapeutic and regenerative prospects in neurological diseases by modulating brain activity and improving cognitive and motor functions.Given the paucity of knowledge about the underlying modes of action and optimal treatment modalities,a thorough translational investigation of noninvasive brain stimulation in preclinical animal models is urgently needed.Thus,we reviewed the current literature on the mechanistic underpinnings of noninvasive brain stimulation in models of central nervous system impairment,with a particular emphasis on traumatic brain injury and stroke.Due to the lack of translational models in most noninvasive brain stimulation techniques proposed,we found this review to the most relevant techniques used in humans,i.e.,transcranial magnetic stimulation and transcranial direct current stimulation.We searched the literature in Pub Med,encompassing the MEDLINE and PMC databases,for studies published between January 1,2020 and September 30,2024.Thirty-five studies were eligible.Transcranial magnetic stimulation and transcranial direct current stimulation demonstrated distinct strengths in augmenting rehabilitation post-stroke and traumatic brain injury,with emerging mechanistic evidence.Overall,we identified neuronal,inflammatory,microvascular,and apoptotic pathways highlighted in the literature.This review also highlights a lack of translational surrogate parameters to bridge the gap between preclinical findings and their clinical translation.展开更多
基金supported financially by the Excellent Going Abroad Expert's Training Program in Hebei Province (No. 201940)the Hebei Natural Science Foundation of China (No. H2020208030)the S & T Program of Hebei (No. 22567607H) for financial support。
文摘A nickel-catalyzed C(sp^(2))–H alkynylation of unprotected α-substituted benzylamines is achieved by utilizing a transient directing group. The combination of a TDG with a nickel catalyst significantly improves the reaction step and atom economy. It has been investigated that the 2,4,6-trimethylpyridine ligand was critical to achieve the optimized reactivity. This protocol provides a straightforward route for synthesizing the alkynylated free benzylamines, featuring good substrate compatibility and monoselectivity.
基金support from the National Natural Science Foundation of China(No.21901206)Postdoctoral Science Foundation of China(No.2022M712589)+2 种基金General Key R&D Projects in Shaanxi Province(No.2023-YBGY-321)Natural Science Foundation of Chongqing(No.CSTB2022NSCQ-MSX0826)National&Local Joint Engineering Research Center for mineral Salt Deep Utilization,Huaiyin Institute of Technology(No.SF202407)for financial support。
文摘The transition metal-catalyzed C–H activation have been considered as increasingly useful approach for installing new functional groups onto organic small molecules due to their high step-and atom-economy,the abundance of hydrocarbon compounds,and the potential for late-stage functionalization of complex organic molecules.The ortho-and meta-C-H activation and functionalization of aromatic compounds have been widely explored in recent years,however the distal para-C-H activation and functionalization has remained a significant challenge because of the difficulty in forming energetically favorable metallacyclic transition states.The utilization of appropriate directing groups or templates as well as the meticulous design of catalysts and ligands has proven to be effective in transition-metal-catalyzed remote para-C-H bonds activation and functionalization of aromatic compounds.This review aims to summarize the strategies for controlling para-selective C–H functionalization using the directing group,template engineering,and catalyst/ligand design under transition metals catalysis in recent years.
基金Department of Envirenmental Medicine, Bethune University of Medical Sciences
文摘The directing mechanisms of liquid directing agents of zeolite Y and zeolite L were studied by means of light transmission, ultracentrifugation, NMR, XRD and “cross-exchange” experiments. It was discovered that not only microcfystals of zeolites, but also cage structures of zeolites play the directing role for crystallization of zeolites.
文摘In this work,we show for the first time that high-silica zeolites(MFI,TON,MTT,and*MRE)could be synthesized from a combined strategy of both zeolite seeding and alcohol filling in the absence of organic structure-directing agents(OSDAs).High-silica ZSM-5 zeolites with Si/Al ratios ranging from 38 to 240(TF-Al-ZSM-5)could be synthesized via this route.The key to the success of this technique was the employment of an aluminosilicate precursor with a fully 4-coordinated aluminum species as the initial source,wherein the rearrangement and condensation of the silicate species,rather than the aluminate species,occurred during zeolite crystallization.In addition,heteroatoms,such as Fe and B,could be incorporated into the zeolite frameworks.Catalytic tests for the methanol-to-propylene(MTP)reaction exhibited good catalytic performance for TF-Al-ZSM-5,which was comparable to that of the aluminosilicate ZSM-5 zeolite synthesized with OSDAs.Hence,this method offers viable opportunities for the industrial production and catalytic application of high-silica zeolites in the future.
基金supported by the National Natural Science Foundation of China(Grant No.21802136)~~
文摘Zeolite synthesis in contemporary chemical industries is predominantly conducted using organic structure‐directing agents(OSDAs),which are chronically hazardous to humans and the environment.It is a growing trend to develop an eco‐friendly and nuisanceless OSDA for zeolite synthesis.Herein,choline is employed as a non‐toxic and green OSDA to synthesize high silica Y zeolite with SiO2/Al2O3 ratios of 6.5–6.8.The prepared Y zeolite samples exhibited outstanding(hydro)thermal stability at ultrahigh temperature owing to the higher SiO2/Al2O3 ratio.The XRF,SEM,29Si‐NMR and 13Na+results suggested that choline plays a structure‐directing role in the synthesis of Y zeolite,while the feed molar fraction of Na+is a crucial determinant for the framework SiO2/Al2O3 ratio and the crystal morphology.
基金the financial support from the National Natural Science Foundation of China(No.20973022 and No.11472048)the State Key Laboratory of Catalytic Materials and Reaction Engineering(RIPP,SINOPEC)(Serial No.33600000-14-ZC0607-0006)
文摘Zeolite FAU composites with a macro/meso-microporous hierarchical structure were hydrothermally synthesized using macro-mesoporous γ-Al_2O_3 monolith as the substrate by means of the liquid crystallization directing agent(LCDA) induced method. No template was needed throughout the synthesis processes. The structure and porosity of zeolite composites were analyzed by means of X-ray powder diffraction(XRD), scanning electron microscopy(SEM) and N_2adsorption-desorption isotherms. The results showed that the supported zeolite composites with varied zeolitic crystalline phases and different morphologies can be obtained by adjusting the crystallization parameters, such as the crystallization temperature, the composition and the alkalinity of the precursor solution. The presence of LCDA was defined as a determinant for synthesizing the zeolite composites. The mechanisms for formation of the hierarchically porous FAU zeolite composites in the LCDA induced synthesis process were discussed. The resulting monolithic zeolite with a trimodal-porous hierarchical structure shows potential applicability where facile diffusion is required.
基金financially supported by the National Natural Science Foundation of China(No.21861030)the Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(No.NJYT-17-A22)。
文摘Reported herein is the first example of heterogeneous palladium catalyzed C(sp^(3))-H bonds arylation by a transient-ligand-directed strategy.Using supported palladium(metallic state) na nopariticles as catalyst,a wide range of aryl iodides undergo the coupling with various o-methylbenzaldehyde derivatives to assemble a library of highly selective and functionalized o-benzylbenzaldehydes.The stability of the catalyst was easily recovered four runs without significant loss of activity.The XPS analysis of the catalyst before and after reaction indicated that the reaction might be carried out by a catalytic cycle starting with Pd~0.
基金We thank the National Natural Science Fund of China(2016-Z0030)Natural Science Foundation of Liaoning Province(L2017 LQN008,L2019014).
文摘Silicoaluminophosphates SAPO-11 molecular sieves with small particle size and hierarchical pores were synthesized using the directing agent method.The effect of crystallization time on the particle structure,morphology,pore structure properties,and acid properties of SAPO-11 molecular sieves were investigated.Unlike the SAPO-11 molecular sieves synthesized with the conventional method,the results of XRD,SEM,BET and NH3-TPD analyses showed that the SAPO-11 molecular sieves synthesized by the directing agent method in a shorter crystallization time exhibited fine and uniform morphology.By increasing the crystallization time,the particle size of SAPO-11 molecular sieve was significantly reduced,and the mesoporous structure(intercrystalline pores)was formed.Furthermore,the external specific surface area and the total specific surface area reached 81.7 m^2/g and 192.0 m^2/g,respectively,which effectively reduced the pore mass transfer resistance and significantly increased the number of acid sites.The results of n-dodecane hydroisomerization revealed that the Pt/SAPO-11 prepared with the novel method exhibited higher catalytic activity and better hydroisomerization selectivity than that synthesized by the conventional hydrothermal method.Thus,the small particle molecular sieve showed a promising industrial application prospect to be used as catalyst support.
基金the NSFC(Nos.21372178 and 21572163)for financial supportsupported by the Scientific Innovation Program for College Students of Zhejiang Province(No. 2016R426061)
文摘In this review, we highlight the recent development in Ru（II）-catalyzed C-H activations under redox neutral conditions. After a brief introduction of the C-H activations with oxidizing direct group by different transition metal catalysts, the examples with Ru（ll） catalyst were classified and introduced according to different internal oxidants used in the system. The features of each methodology will be highlighted and the plausible reaction mechanism will be presented if available.
文摘Article 1 These regulations are formulated according to the rules of the State Law on foreign investment and the requirements of industrial policies to direct foreign investment, ensuring that it adapts to the programmes of China’s national economy and social development and protecting the legal rights and interests of investors.
基金Shandong Major Science and Technology Innovation Projects(2018CXGC0203)National Special Vegetable Industry Technology System Project(CARS-24-D-01)Shandong Agricultural University“Double-first-class”Collaborative Innovation Team of Horticultural Machinery Equipment(SYL2017XTTD07).
文摘Garlic planting requires a single seed with a scaly bud upward and vertically.In this study,an automatic garlic seed directing device was designed for auxiliary garlic seeding by utilizing a seed placed funnel,a correcting mechanism,and an automatic control system.Three factors influenced device performance:characteristics of garlic seeds,limited notch diameter of the seed placed funnel,and funnel taper of the seed placed funnel.The most optimal structural parameters of the seed placed funnel were determined via theoretical analysis.The research samples of Lanling and Jinxiang garlic were divided into three groups according to their respective sizes.3D design software(Solidworks)was used to simulate the above three factors and analyze their rules of action.The obtained simulation results demonstrated that the suitable range of funnel taper and limited notch diameter of seed placed funnel for the three groups of seed were from 40°to 60°and 6-8 mm,respectively.The bench test showed that when the funnel taper was 60°and the limited notch diameter was 10 mm,the success rates of the three groups’seeds in terms of scaly bud directing were 89.8%,91.6%and 96.6%respectively,which satisfied the agricultural requirements of garlic planting.Accordingly,the corresponding results may promote the study and improvement of garlic intelligent planting equipment.
基金Acknowledgement We thank National Basic Research Program of China （973 Program） （No. 2015CB856600）, the National Natural Science Foundation of China （Nos. 21632001, 21772002）, National Young Topnotch Talent Support Program, and Peking University Health Science Center （No. BMU20160541） for financial support of this work. We thank Bencong Zhu in this group for reproducing the results of 3b and 4f.
文摘Transition-metal catalyzed C--H functionalization of benzaldehydes is of great interest in organic synthesis. Herein, we developed a transient directing group assisted amidation of benzaldehydes catalyzed by rhodium catalyst. With the employment of 10 mol% of 4-trifluoromethyl aniline, the in situ generated imine groups as the directing group efficiently enable this transformation. By using this protocol, a wide range of benzaldehydes were efficiently converted into the corresponding N-（2-formylphenyl）benzamides utilizing dioxazolones as the nitrogen source.
文摘The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion.
基金Project supported by the National Natural Science Foundation of China.
文摘In this paper we give the criteria and constructions of directing compo-nents of a representation-infinite algebra,and the structure of a trivial extension algebraT(A)having Z-component,where A is an iterated-tilted algebra.
基金supported by the National Natural Science Foundation of China (21925109, 21772170)the Outstanding Young Talents of Zhejiang Province High-level Personnel of Special Support (ZJWR0108)+1 种基金the Fundamental Research Funds for the Central Universities (2018XZZX001-02)Zhejiang Provincial Natural Science Foundation (LR17B020001)。
文摘A strategy for Pd-catalyzed ortho-C–H silylation of biaryl aldehydes enabled by a transient auxiliary is presented. This protocol provides a broad range of ortho-silylated biaryl aldehydes in good yields. The silyl moiety can be further functionalized under mild conditions, rendering the silylated products useful building blocks. Notably, this protocol also offers an opportunity to establish a platform for expeditious synthesis of structurally diverse axially chiral biaryl aldehydes via sequential atroposelective interannular C–H functionalization/intraanular C–H silylation.
文摘BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level.
基金funded by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation):project ID 431549029-SFB 1451the Marga-und-Walter-Boll-Stiftung(#210-10-15)(to MAR)a stipend from the'Gerok Program'(Faculty of Medicine,University of Cologne,Germany)。
文摘Noninvasive brain stimulation techniques offer promising therapeutic and regenerative prospects in neurological diseases by modulating brain activity and improving cognitive and motor functions.Given the paucity of knowledge about the underlying modes of action and optimal treatment modalities,a thorough translational investigation of noninvasive brain stimulation in preclinical animal models is urgently needed.Thus,we reviewed the current literature on the mechanistic underpinnings of noninvasive brain stimulation in models of central nervous system impairment,with a particular emphasis on traumatic brain injury and stroke.Due to the lack of translational models in most noninvasive brain stimulation techniques proposed,we found this review to the most relevant techniques used in humans,i.e.,transcranial magnetic stimulation and transcranial direct current stimulation.We searched the literature in Pub Med,encompassing the MEDLINE and PMC databases,for studies published between January 1,2020 and September 30,2024.Thirty-five studies were eligible.Transcranial magnetic stimulation and transcranial direct current stimulation demonstrated distinct strengths in augmenting rehabilitation post-stroke and traumatic brain injury,with emerging mechanistic evidence.Overall,we identified neuronal,inflammatory,microvascular,and apoptotic pathways highlighted in the literature.This review also highlights a lack of translational surrogate parameters to bridge the gap between preclinical findings and their clinical translation.
