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New strategies for asymmetric photocatalysis: asymmetric organocatalytic/photoredox relay catalysis for efficient synthesis of polycyclic compounds containing vicinal amino alcohols

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Science China Chemistry 2024年第3期67卷 945-952页

作者： Jia-Lu Zhang Wen-bo He xiu-qin Hu Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Veterinary Etiological Biology College of Veterinary MedicineLanzhou UniversityLanzhou Veterinary Research InstituteChinese Academy of Agricultural SciencesLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China

An asymmetric catalytic strategy in photocatalysis utilizing a chirality-induced approach through an organocatalytic/photoredox relay catalysis strategy is successfully achieved for the rapid construction of polycyclic compounds containing vicinal amino alcohols in a one-pot protocol. This methodology facilitates the efficient synthesis of diverse substituted polycyclic tetrahydroquinoline and benzofuran-derived vicinal amino alcohols, each containing five consecutive chiral centers, with high yields,excellent diastereoselectivities and enantioselectivities(up to 95% yield, >20:1 dr and 98% ee), under mild reaction conditions driven by sequential bifunctional squaramide organocatalyst-catalyzed [4+2] annulation and photocatalyst-catalyzed ketyl radical addition cyclization reaction process. Furthermore, investigations into the stereoselectivity mechanism and high-resolution mass spectrometry(HRMS) experiments on free radical trapping have provided evidence for elucidating the detailed mechanism of chirality-induced processes and chiral intermediate conversions in this procedure.

关键词： enantioselective photocatalysis asymmetric organocatalytic/photocatalysis relay catalysis five consecutive chiral centers chirality-induced strategy chirality vicinal amino alcohols

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Chinese Physics Letters 2012年第4期29卷 206-209页

作者： LI Yue DENG Ai-Hong ZHOU Yu-Lu ZHOU Bing WANG Kang HOU qing SHI Li-Qun qin xiu-bo WANG Bao-Yi Department of Physics Sichuan UniversityChengdu 610064 Key Laboratory of Radiation Physics and Technology of Ministry of Education Institute of Nuclear Science and TechnologySichuan UniversityChengdu 610064 Institute of Modern Physics Fudan UniversityShanghai 200433 Laboratory of Nuclear Analysis Technique Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049

Various helium-containing titanium films were deposited on Si substrates by magnetron sputtering under different helium/argon (He/Ar) *** concentrations and corresponding depth profiles in the Ti films are obtained by elastic recoil detection analysis (ERDA).X-ray diffraction (XRD) measurements are carried out to evaluate the crystallization of the titanium ***-type defects and their depth profiles were revealed by slow positron beam analysis (SPBA).It is found that the defect-characteristic parameter S rises with the increment of the He/Ar flow *** variation of S indicates the formation and evolution of various Herelated defects,with uniform distribution into the depth around 400nm.

关键词： titanium Titanium increment

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In situ meso-tetra(4-carboxyphenyl)porphyrin ligand substitution in Hf-MOF for enhanced catalytic activity and stability in photoredox reactions

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Rare Metals 2024年第6期43卷 2682-2694页

作者： Jie Hu Hong-Xin Lao xiu-Wu Xu Wei-Kang Wang Le-Le Wang qin-qin Liu School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China College of Chemistry and Materials Engineering Research Center of Carbon NeutralityAnhui Normal UniversityWuhu 241002China Fujian Provincial Key Laboratory of Ecology-Toxicological Effects and Control for Emerging Contaminants Putian UniversityPutian 351100China

Though there are numerous intrinsic merits of metal-organic frameworks(MOFs),low charge separation efficiency has imposed heavy restrictions on their photocatalytic ***,in situ porphyrin ligand substitution,as a strategy for improving the charge separation efficiency and increasing the amounts of active sites,has been designed and realized in a Hf-biphenyl dicarboxylic acid(BPDC)***,a size and geometry matched meso-tetra(4-carboxyphenyl)porphyrin(TCPP)ligand was selected and doped into Hf-BPDC MOF by forming coordinating bonds with Hf centers,forming dualligand Hf-BPDC-TCPP *** resultant Hf-BPDC-TCPP MOF showed significantly improved activity and chemical stability in the photocatalytic H_(2)generation(261μmol·g^(-1)·h^(-1))and tetracycline(TC)degradation reactions(95.8%),which was 48 and 1.47 folds higher than that of the Hf-BPDC *** and electrochemical studies revealed that the introduction of porphyrin ligand could generate a stronger internal electric field for boosting the charge separation and transfer,increase the specific surface area for providing more active sites,and narrow the band gap to enhance the visible light *** in situ ligand substitution method provides a promising approach to build a tunable platform for constructing high-performance MOF photocatalysts.

关键词： Ligand substitution Metal organic frameworks Meso-tetra(4-carboxyphenyl)porphyrin Hydrogen evolution reaction Tetracycline degradation

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On Depolymerization

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CCS Chemistry 2024年第2期6卷 297-312页

作者： bo qin Xi Zhang College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082 Department of Chemistry Tsinghua UniversityBeijing 100084

Polymers have become an essential part of modern life and the global economy on account of their costeffectiveness and versatile ***,most postconsumer polymer wastes are unrecycled,leading to environmental pollution and resource ***,as an efficient chemical recycling approach,holds great promise in establishing a circular polymer *** this review,we attempt to highlight recent and significant advancements in depolymerization *** key research topics are discussed:(1)depolymerization of commodity polymers to produce reusable monomers and high-value chemicals;(2)depolymerization of intrinsically depolymerizable *** is anticipated that this review will reflect the present status and future trends of this rapidly evolving realm of depolymerization.

关键词： depolymerization chemical recycling sustainable polymers circular polymer economy catalysis dynamic covalent chemistry

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Central environmental protection inspection and carbon emission reduction: A tripartite evolutionary game model from the perspective of carbon neutrality

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Petroleum Science 2024年第3期21卷 2139-2153页

作者： Zhen-Hua Zhang Dan Ling qin-Xin Yang Yan-Chao Feng Jing xiu School of Economics Lanzhou UniversityLanzhou 730000GansuChina Institute of Green Finance Lanzhou UniversityLanzhou 730000GansuChina School of Management Lanzhou UniversityLanzhou 730000GansuChina School of Business Zhengzhou UniversityZhengzhou 450001HenanChina Institute of Economics Jilin Academy of Social SciencesChangchun130033JilinChina

Since the carbon neutrality target was proposed,many countries have been facing severe challenges to carbon emission reduction *** study is conducted using a tripartite evolutionary game model to explore the impact of the central environmental protection inspection(CEPI)on driving carbon emission reduction,and to study what factors influence the strategic choices of each party and how they interact with each *** research results suggest that local governments and manufacturing enterprises would choose strategies that are beneficial to carbon reduction when CEPI *** the initial willingness of all parties increases 20%,50%—80%,the time spent for the whole system to achieve stability decreases from 100%,60%—30%.The evolutionary result of“thorough inspection,regulation implementation,low-carbon management”is the best strategy for the tripartite evolutionary ***,the smaller the cost and the larger the benefit,the greater the likelihood of the three-party game stability strategy *** study has important guiding significance for other developing countries to promote carbon emission reduction by environmental policy.

关键词： Central environmental protection inspection Local government Manufacturing enterprise Tripartite evolutionary game Carbon emission reduction

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Circulating DNA level is negatively associated with the long-term survival of hepatocellular carcinoma patients

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World Journal of Gastroenterology 2006年第24期12卷 3911-3914页

作者： Ning Ren qing-Hai Ye Lun-xiu qin bo-Heng Zhang Yin-Kun Liu Zhao-YouTang Liver Cancer Institute and Zhongshan Hospital Fudan University 180 Feng Lin Road Shanghai 200032 China

AIM： To quantify the circulating DNA in plasma from patients with hepatocellular carcinoma （HCC） and to evaluate its prognostic value. METHODS： Blood samples were collected from 79 patients with HCC before operation, 20 patients with liver cirrhosis, and 20 healthy volunteers. Circulating DNA was extracted from plasma and quantified. The association between circulating DNA level and prognosis of HCC patients was evaluated. RESULTS： Compared with the healthy volunteers （17.6 ± 9.5 ng/mL）, a significant higher circulating DNA level was found in the patients with HCC （47.1 ± 43.7 ng/ mL, P = 0.000） or with liver cirrhosis （30.0 ± 13.3 ng/ mL, P = 0.002）. The circulating DNA level was closely associated with tumor size （P = 0.008） and TNM stage （P = 0.040）, negatively associated with the 3-year diseasefree survival （DFS）（P = 0.017） and overall survival （OS）（P = 0.001）. CONCLUSION： Large or invasive tumor may release more circulating DNA, and higher level of circulating DNA may be associated with poor prognosis of HCC patients.

关键词： Hepatocellular carcinoma Prognosis Circulating DNA

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Enhanced Sensing Mechanism Based on Shifting an Exceptional Point

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Research 2024年第3期6卷 285-292页

作者： Xuan Mao Guo-qing qin Hao Zhang bo-Yang Wang Dan Long Gui-qin Li Gui-Lu Long Department of Physics State Key Laboratory of Low-Dimensional Quantum PhysicsTsinghua UniversityBeijing 100084China Beijing Institute of Radio Measurement The Second Academy of China Aerospace Science and Industry Corporation(CASIC)Beijing 100854China Purple Mountain Laboratories Nanjing 21111China Frontier Science Center for Quantum Information Beijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100193China

Non-Hermitian systems associated with exceptional points (EPs) are expected to demonstrate a giant response enhancement for various sensors. The widely investigated enhancement mechanism based on diverging from an EP should destroy the EP and further limits its applications for multiple sensing scenarios in a time sequence. To break the above limit, here, we proposed a new enhanced sensing mechanism based on shifting an EP. Different from the mechanism of diverging from an EP, our scheme is an EP nondemolition and the giant enhancement of response is acquired by a slight shift of the EP along the parameter axis induced by perturbation. The new sensing mechanism can promise the most effective response enhancement for all sensors in the case of multiple sensing in a time sequence. To verify our sensing mechanism, we construct a mass sensor and a gyroscope with concrete physical implementations. Our work will deepen the understanding of EP-based sensing and inspire designing various high-sensitivity sensors in different physical systems.

关键词： mechanism shifting exceptional

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QBIoT:A Quantum Blockchain Framework for IoT with an Improved Proof-of-Authority Consensus Algorithm and a Public-Key Quantum Signature

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Computers, Materials & Continua 2024年第7期80卷 1727-1751页

作者： Ang Liu qing Zhang Shengwei Xu Huamin Feng xiu-bo Chen Wen Liu Network and Information Management Division Beijing Electronic Science and Technology InstituteBeijing100070China Department of Cyberspace Security Beijing Electronic Science and Technology InstituteBeijing100070China Information Security Institute Beijing Electronic Science and Technology InstituteBeijing100070China General Office Beijing Electronic Science and Technology InstituteBeijing100070China Information Security Center State Key Laboratory of Networking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing100876China

The Internet of Things(IoT)is a network system that connects physical devices through the Internet,allowing them to ***,IoT has become an integral part of our lives,offering convenience and smart ***,the growing number of IoT devices has brought about a corresponding increase in cybersecurity threats,such as device vulnerabilities,data privacy concerns,and network *** blockchain technology with IoT has proven to be a promising approach to enhance IoT ***,the emergence of quantum computing poses a significant challenge to the security of traditional classical cryptography used in blockchain,potentially exposing it to quantum *** support the growth of the IoT industry,mitigate quantum threats,and safeguard IoT data,this study proposes a robust blockchain solution for IoT that incorporates both classical and post-quantum security ***,we present the Quantum-Enhanced Blockchain Architecture for IoT(QBIoT)to ensure secure data sharing and integrity ***,we propose an improved Proof of Authority consensus algorithm called“Proof of Authority with Random Election”(PoARE),implemented within QBIoT for leader selection and new block ***,we develop a publickey quantum signature protocol for transaction verification in the ***,a comprehensive security analysis of QBIoT demonstrates its resilience against cyber threats from both classical and quantum *** summary,this research introduces an innovative quantum-enhanced blockchain solution to address quantum security concernswithin the realmof *** proposedQBIoT framework contributes to the ongoing development of quantum blockchain technology and offers valuable insights for future research on IoT security.

关键词： IoT quantum blockchain public-key quantum signature quantum hash function

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Reactive transport modeling constraints on the complex genesis of a lacustrine dolomite reservoir: A case from the Eocene Qaidam Basin,China

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Petroleum Science 2024年第4期21卷 2240-2256页

作者： Ying Xiong bo Liu xiu-Cheng Tan Zheng-Meng Hou Jia-Shun Luo Ya-Chen Xie Kai-bo Shi Kun-Yu Wu School of Earth and Space Sciences Peking University Institute of Oil and Gas Peking University China National Petroleum Corporation Key Laboratory of Carbonate Reservoirs Southwest Petroleum University Institute of Subsurface Energy Systems Clausthal University of Technology Research Institute of Exploration and Development PetroChina Qinghai Oil Field Company

Reactive transport modeling(RTM) is an emerging method used to address geological issues in diagenesis research. However, the extrapolation of RTM results to practical reservoir prediction is not sufficiently understood. This paper presents a case study of the Eocene Qaidam Basin that combines RTM results with petrological and mineralogical evidence. The results show that the Eocene Xiaganchaigou Formation is characterized by mixed siliciclastic-carbonate-evaporite sedimentation in a semiclosed saline lacustrine environment. Periodic evaporation and salinization processes during the syngeneticpenecontemporaneous stage gave rise to the replacive genesis of dolomites and the cyclic enrichment of dolomite in the middle-upper parts of the meter-scale depositional sequences. The successive change in mineral paragenesis from terrigenous clastics to carbonates to evaporites was reconstructed using RTM simulations. Parametric uncertainty analyses further suggest that the evaporation intensity(brine salinity) and particle size of sediments(reactive surface area) were important rate-determining factors in the dolomitization, as shown by the relatively higher reaction rates under conditions of higher brine salinity and fine-grained sediments. Combining the simulation results with measured mineralogical and reservoir physical property data indicates that the preservation of original intergranular pores and the generation of porosity via replacive dolomitization were the major formation mechanisms of the distinctive lacustrine dolomite reservoirs(widespread submicron intercrystalline micropores) in the Eocene Qaidam Basin. The results confirm that RTM can be effectively used in geological studies, can provide a better general understanding of the dolomitizing fluid-rock interactions, and can shed light on the spatiotemporal evolution of mineralogy and porosity during dolomitization and the formation of lacustrine dolomite reservoirs.

关键词： Reactive transport modeling Lacustrine dolomite Mineralogy and porosity evolution Reservoir genesis

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The role of cholesterol metabolism in lung cancer

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Oncology Research 2024年第10期32卷 1613-1621页

作者： WEIGANG xiu XINGYU LIU KAIXIN HU qin ZHANG HUASHAN SHI Department of Thoracic Oncology and State Key Laboratory of Biotherapy Cancer CenterWest China HospitalSichuan UniversityChengdu610041China West China School of Medicine Sichuan UniversityChengdu610041China Department of Postgraduate Students West China School of MedicineChengdu610041China Department of Biotherapy Cancer CenterWest China HospitalSichuan UniversityChengdu610041China

Elevated serum cholesterol metabolism is associated with a reduced risk of lung *** cholesterol metabolism is evident in both lung cancer patients and tumor *** tumor cell cholesterol uptake or biosynthesis pathways,through the modulation of receptors and enzymes such as liver X receptor and sterolregulatory element binding protein 2,effectively restrains lung tumor ***,promoting cholesterol excretion yields comparable *** metabolites,including oxysterols and isoprenoids,play a crucial role in regulating cholesterol metabolism within tumor cells,consequently impacting cancer *** lung cancer patients,both the cholesterol levels in the tumor microenvironment and within tumor cells significantly influence cell growth,proliferation,and *** effects of cholesterol metabolism are further mediated by the reprogramming of immune cells such as T cells,B cells,macrophages,myeloid-derived suppressor cells,among *** research is investigating drugs targeting cholesterol metabolism for clinical ***,targeting the cholesterol biosynthesis pathway,are widely employed in lung cancer treatment,either as standalone agents or in combination with other ***,drugs focusing on cholesterol transportation have shown promise as effective therapies for lung *** this review,we summarized current research regarding the rule of cholesterol metabolism and therapeutic advances in lung cancer.

关键词： Cholesterol metabolism Lung cancer Immune cells Targeted strategies

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