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Chinese Journal of Chemistry 2024年第8期42卷 873-878页

作者： Jian Long Zhiwu Lu Xiao-Lin Li Peng Xue Wen-bo liu Engineering Research Center of Organosilicon Compounds&Materials(Ministry of Education)and College of Chemistry and Molecular Sciences Wuhan UniversityWuhanHubei430072 China

Comprehensive Summary,The azepine ring is a prominent structural scaffold in biologically significant molecules. In this study, we present a Ni(II)-catalyzed asymmetric difunctionalization of alkynes, involving intermolecular regioselective arylation and intramolecular nitrile addition, enabling the synthesis of enantioenriched azepine derivatives. This reaction simultaneously installs an all-carbon quaternary stereocenter and introduces an unprotected imine functionality, showing great promise for subsequent transformations. The reaction exhibits good tolerance toward various functional groups, resulting in high yields and enantioselectivities. The synthetic utility of this methodology is further demonstrated through gram-scale synthesis and product derivatization. This research offers an efficient approach to the synthesis of seven-membered nitrogen heterocycles.

关键词： Nickel Asymmetric catalysis N-Heterocycles Alkyne functionalization Quaternary centers

A green cross-linking method for the preparation of renewable threedimensional graphene sponges for efficient adsorption of Congo red dye

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Chinese Journal of Chemical Engineering 2024年第2期66卷 84-93页

作者： Zhuang liu bo Gao Haoyuan Han Yuling Li Haiyang Fu Donghui Wei Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China

Graphene-based materials possess significant potential for the treatment of dye wastewater due to their exceptional adsorption properties toward stubborn ***,their utilization is hindered by high preparation costs,low yields,environmental pollution during synthesis,and challenges in regenerating the *** study proposes a novel approach to address these limitations by developing nitrogen-doped three-dimensional(3D)polyvinyl alcohol(PVA)crosslinked graphene sponges(N-PGA)using a cross-linking method with ammonium *** method offers a relatively mild,environmentally friendly *** carbonate serves as both a reducing and modifying agent,facilitating the formation of the intrinsic structure of N-PGA and acting as a nitrogen ***,PVA is utilized as the cross-linking *** results demonstrate that N-PGA exhibits a favorable internal 3D hierarchical porous structure and possesses robust mechanical *** measured specific surface area(BET)of N-PGA was as high as406.538 m^(2)·g^(-1),which was favorable for its efficient adsorption of Congo red(CR)dye *** an initial concentration of 50 mg·L^(-1),N-PGA achieved an impressive removal rate of 89.6%and an adsorption capacity of 112 mg·g^(-1)for CR ***,it retained 79%of its initial adsorption capacity after 10 cycles,demonstrating excellent regeneration *** summary,the synthesized N-PGA displays remarkable efficacy in the adsorption of CR dye in wastewater,opening up new possibilities for utilizing 3D porous graphene nanomaterials as efficient adsorbents in wastewater treatment.

关键词： Green chemistry Graphene sponge Adsorbents Adsorption Congo red Regeneration

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

Vibration and noise mechanism of a 110 kV transformer under DC bias based on finite element method

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Global Energy Interconnection 2024年第4期7卷 503-512页

作者： Ziyang Li Xujun Lang bo Yang Xiaolin liu Hao Wang Zhang Li Shandong Electric Power Engineering Consulting Institute Co. Ltd.Jinan 250013P.R.China School of Electrical Engineering Shandong UniversityJinan 250061P.R.China

Global energy and environmental issues are becoming increasingly problematic,and the vibration and noise problem of 110 kV transformers,which are the most widely distributed,have attracted widespread attention from both inside and outside the *** bias is one of the main contributing factors to vibration noise during the normal operation of *** clarify the vibration and noise mechanism of a 110 kV transformer under a DC bias,a multi-field coupling model of a 110 kV transformer was established using the finite element *** electromagnetic,vibration,and noise characteristics during the DC bias process were compared and quantified through field circuit coupling in parallel with the power frequency of AC,harmonic,and DC power *** was found that a DC bias can cause significant distortions in the magnetic flux density,force,and displacement distributions of the core and *** contributions of the DC bias effect to the core and winding are different at Kdc=*** this point,the core approached saturation,and the increase in the core force and displacement ***,the saturation of the core increased the leakage flux,and the stress and displacement of the winding increased *** sound field distribution characteristics of the 110 kV transformer under a DC bias are related to the force *** the DC bias coefficient was 1.25,the noise sound pressure level reached 73.6 dB.

关键词： Transformer DC bias Vibration Noise

Pathology of pain and its implications for therapeutic interventions

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2851-2899页

作者： bo Cao Qixuan Xu Yajiao Shi Ruiyang Zhao Hanghang Li Jie Zheng Fengyu liu You Wan bo Wei Department of General Surgery First Medical CenterChinese PLA General HospitalBeijing 100853China Medical School of Chinese PLA Beijing 100853China Neuroscience Research Institute and Department of Neurobiology School of Basic Medical SciencesKey Laboratory for NeuroscienceMinistry of Education/National Health CommissionPeking UniversityBeijing 100191China

Pain is estimated to affect more than 20%of the global population,imposing incalculable health and economic *** pain management is crucial for individuals suffering from ***,the current methods for pain assessment and treatment fall short of clinical *** from advances in neuroscience and biotechnology,the neuronal circuits and molecular mechanisms critically involved in pain modulation have been *** research achievements have incited progress in identifying new diagnostic and therapeutic *** this review,we first introduce fundamental knowledge about pain,setting the stage for the subsequent *** review next delves into the molecular mechanisms underlying pain disorders,including gene mutation,epigenetic modification,posttranslational modification,inflammasome,signaling pathways and *** better present a comprehensive view of pain research,two prominent issues,sexual dimorphism and pain comorbidities,are discussed in detail based on current *** status quo of pain evaluation and manipulation is summarized.A series of improved and innovative pain management strategies,such as gene therapy,monoclonal antibody,brain-computer interface and microbial intervention,are making strides towards clinical *** highlight existing limitations and future directions for enhancing the quality of preclinical and clinical *** to decipher the complexities of pain pathology will be instrumental in translating scientific discoveries into clinical practice,thereby improving pain management from bench to bedside.

关键词： pain thereby summarized

Association between MTHFR c.677C>T variant and erectile dysfunction among males attending fertility clinic

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Asian Journal of Andrology 2024年第1期26卷 41-45页

作者： Shun Bai Ming-Zhen Li Yang-Yang Wan Xue-Chun Hu Yi-Xun liu Xian-hong Tong Tong-Hang Guo Lu Zong Ran liu Yuan-Qi Zhao Ping Xiang bo Xu Xiao-Hua Jiang Department of Gynecology and Obstetrics Reproductive and Genetic HospitalThe First Affiliated Hospital of University of Science and Technology of ChinaDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China NHC Key Laboratory of Male Reproduction and Genetics Guangdong Provincial Reproductive Science Institute(Guangdong Provincial Fertility Hospital)Guangzhou 510600China Department of Urology The First Affiliated Hospital of University of Science and Technology of ChinaDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Wannan Medical College Wuhu 241002China

Genetic risk factors have been shown to contribute to the development of sexual ***,the role of methylenetetrahydrofolate reductase(MTHFR)gene variants in the risk of erectile dysfunction(ED)remains *** this study,we recruited 1254 participants who underwent ED assessed by the International Index of Erectile *** MTHFR c.677C>T variant was also measured by fluorescence polymerase chain reaction(PCR).No significant difference in the genotypic frequency of the MTHFR C677T polymorphism(CC,CT,and TT)was observed between men from the ED and non-ED *** addition,on binary logistic regression analysis,both crude and adjusted models showed that the risk of ED was not significantly associated with the C677T ***,a significantly higher frequency of the 677TT polymorphism was found in severe and moderate ED(P=O.02).The positive correlation between the MTHFR 677TT polymorphism and severe ED was confirmed by logistic regression analysis,even after adjusting for potential confounders(odds ratio[OR]=2.46,95%confidence interval[CI]:1.15-5.50,P=0.02).These findings suggest a positive correlation between the MTHFR 677TT polymorphism and the risk of severe *** of MTHFR gene polymorphisms may provide complementary information for ED patients during routineclinicaldiagnosis.

关键词： erectile dysfunction gene variant genetic risk factors methylenetetrahydrofolate reductase sexual function

Thiazoloisoindigo-based Polymer Semiconductors: Synthesis,Structure-Property Relationship, Charge Carrier Polarity, and Field-Effect Transistor Performance

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Chinese Journal of Polymer Science 2024年第1期42卷 24-31,I0006页

作者： bo-Wen Li Miao Xiong Mei-Hua liu Zhi-Gao Li Long Sang Zi-Han Xiong Biao Xiao Jian Pei Xiao-bo Wan Key Laboratory of Optoelectronic Chemical Materials and Devices Ministry of EducationSchoolofOptoelectronic Materials&TechnologyJianghan UniversityWuhan430056China Bejing National Laboratoryfor Molecular Sciences the Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Developing new polymeric semiconductors with excellent device performance is essential for organic electronics. Herein, we synthesized two new thiazoloisoindigo(Tz II)-based polymers, namely, P(Tz II-d Th-d Th) and P(Tz II-d Th-d Tz), by copolymerizing thiophene-flanked Tz II with bithiophene and bithiazole, respectively. Owing to the more electron-deficient nature of bithiazole than bithiophene, P(Tz II-d Th-d Tz)possesses deeper LUMO/HOMO levels of-3.45/-5.47 e V than P(Tz II-d Th-d Th)(-3.34/-5.32 e V). The organic field-effect transistor(OFET) devices based on P(Tz II-d Th-d Th) exhibited p-type behaviors with an average hole mobility value as high as 1.43 cm^(2)·V^(-1)·s^(-1), while P(Tz II-d Th-d Tz)showed typical ambipolar characteristics with average hole and electron mobilities of 0.38 and 0.56 cm^(2)·V^(-1)·s^(-1). In addition, we compared the performances of both polymers with other Tz II-based polymers reported in our previous work, and showed that the charge carrier polarity can be manipulated by adjusting the number of the thiophene units between the acceptor unit. As the increase of the number of thiophene rings,charge carrier polarity shifts from electron-dominated ambipolar transport to hole-dominated ambipolar transport and then to unipolar hole transport in OFETs, which provides an effective molecular design strategy for further optimization of polymer OFET performance.

关键词： Field-effect transistor Charge carrier polarity Thiazoloisoindigo

Facile fabrication of graphene/g-C_(3)N_(4) for electromagnetic wave absorption

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Nano Research 2024年第3期17卷 1687-1698页

作者： Qiang Su Yunfei He Dongdong liu Daguang Li Long Xia Xiaoxiao Huang bo Zhong School of Materials Science and Engineering Harbin Institute of Technology WeihaiWeihai 264209China Weihai Yunshan Technology Co. Ltd.Weihai 264200China State Key Laboratory on Integrated Optoelectronics College of Electronic Science&EngineeringJilin UniversityChangchun 130012China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

With the development of the miniaturization of electronic equipment and lightweight weapon equipment,there are new requirements for electromagnetic wave absorption material(EMWAM).EMWAM has outstanding electromagnetic wave absorption properties and lightweight characteristics become an important direction of *** this study,graphene/g-C_(3)N_(4)(GGCN)EMWAM was first synthesized in situ by simple heat treatment,in which the g-C_(3)N_(4) had a porous structure and dispersed on the surface of *** impedance matching of the GGCN was well adjusted by decreasing the dielectric constant and attenuation constant due to the g-C_(3)N_(4) semiconductor property and the graphite-like *** EMW loss mechanism of GGCN was also analyzed by simulating GGCN’s electric field mode distribution and resistance loss power *** analysis result shows that the distribution of g-C_(3)N_(4) among GGCN sheets can produce more polarization effects and relaxation effects by increasing the lamellar ***,the polarization loss of GGCN could be increased successfully by porous g-C_(3)N_(4).Ultimately,the EMW absorption property of GGCN is optimized significantly,and GGCN exhibits excellent EMW absorption *** the thickness is 2 mm,the effective absorption bandwidth(EAB)can reach 4.6 GHz,and when the thickness is 4.5 mm,the minimum reflection loss(RLmin)at 4.56 GHz can reach-34.69 ***,the practical application of EMWAM was studied by radar cross-section(RCS)simulation,showing that GGCN has a good application prospect.

关键词： graphene/g-C_(3)N_(4) impedance matching simulation analysis dielectric loss excellent electromagnetic wave absorption

Prognostic value of a nomogram model for postoperative liver metastasis of colon cancer

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1055-1065页

作者： De-Xin Cheng Kang-Di Xu Han-bo liu Yi liu Department of Interventional Medicine Zhejiang Provincial People’s Hospital(Affiliated People’s HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina General Surgery Cancer CenterDepartment of Vascular SurgeryZhejiang Provincial People’s Hospital(Affiliated People’s HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina

BACKGROUND Colon cancer is one of the most common malignant tumors of the digestive *** metastasis after colon cancer surgery is the primary cause of death in patients with colon *** To construct a novel nomogram model including various factors to predict liver metastasis after colon cancer *** We retrospectively analyzed 242 patients with colon cancer who were admitted and underwent radical resection for colon cancer in Zhejiang Provincial People’s Hospital from December 2019 to December *** were divided into liver metastasis and non-liver metastasis ***,age,and other general and clinicopathological data(preoperative blood routine and biochemical test indexes)were *** risk factors for liver metastasis were analyzed using singlefactor and multifactorial logistic regression.A predictive model was then constructed and evaluated for *** Systemic inflammatory index(SII),C-reactive protein/albumin ratio(CAR),red blood cell distribution width(RDW),alanine aminotransferase,preoperative carcinoembryonic antigen level,and lymphatic metastasis were different between groups(P<0.05).SII,CAR,and RDW were risk factors for liver metastasis after colon cancer surgery(P<0.05).The area under the curve was 0.93 for the column-line diagram prediction model constructed based on these risk factors to distinguish whether liver metastasis occurred *** actual curve of the column-line diagram predicting the risk of postoperative liver metastasis was close to the ideal curve,with good *** prediction model curves in the decision curve analysis showed higher net benefits for a larger threshold range than those in extreme cases,indicating that the model is *** Liver metastases after colorectal cancer surgery could be well predicted by a nomogram based on the SII,CAR,and RDW.

关键词： Systemic immunoinflammatory index C-reactive protein/albumin ratio Erythrocyte distribution width Colon cancer Liver metastasis Novel nomogram model

Enhancement of heavy metals desorption from the soil by eddy deep leaching in hydrocyclone

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Journal of Environmental Sciences 2024年第1期135卷 242-251页

作者： Ning Wang Hao Lu bo liu Tai Xiong Jianping Li Hualin Wang Qiang Yang School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China National Engineering Laboratory for High Concentration Refractory Organic Wastewater Treatment Technology East China University of Science and TechnologyShanghai 200237China

An eddy deep leaching technology was developed in this paper to address the challenge of treating heavy metal contaminants in industrial mining *** desorption effect of As,Cd,Sb and Pb was investigated utilizing chemical leaching and physical eddy *** was found that the heavy metals concentration increased with decreasing particle *** highest proportion of Cd in the form distribution of soil was in the bound to iron and manganese oxides,while the maximum proportion of As,Sb and Pb were in the *** optimal solid-liquid ratio of the hydrocyclone was 1:20,and the corresponding separation efficiency and flow rate were 84.7%and 1.76 m^(3)/hr,*** grade efficiency of soil particle separation increases with particle size and exceeds 99%for particles above 1,000μ*** experiments have revealed that oxalic acid(OA)and a combination of oxalic acid and EDTA(OAPE)were more efficient than citric acid(CA)and a combination of citric acid and EDTA(CAPE)for the desorption of heavy metals,*** comparison of OAPE and eddy leaching found that the latter improved the desorption efficiency by 9.4%,7.5%,7.2%and 7.8%for As,Cd,Sb and Pb compared to the former,*** results demonstrated that the eddy leaching technique could further enhance the desorption efficiency of heavy *** is expected to provide technical support for soil remediation with reduced usage of leaching agents.

关键词： Heavy metals Soil remediation Oxalic acid Eddy leaching Hydrocyclone