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Engineering the coordination structure of Cu for enhanced photocatalytic production of C_(1) chemicals from glucose
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作者 Lulu Sun Shiyang Liu +3 位作者 Taifeng Liu Dongqiang Lei Nengchao Luo Feng Wang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期234-243,共10页
Photocatalytic decomposition of sugars is a promising way of providing H_(2),CO,and HCOOH as sus-tainable energy vectors.However,the production of C_(1) chemicals requires the cleavage of robust C−C bonds in sugars wi... Photocatalytic decomposition of sugars is a promising way of providing H_(2),CO,and HCOOH as sus-tainable energy vectors.However,the production of C_(1) chemicals requires the cleavage of robust C−C bonds in sugars with concurrent production of H_(2),which remains challenging.Here,the photo-catalytic activity for glucose decomposition to HCOOH,CO(C_(1) chemicals),and H_(2) on Cu/TiO_(2)was enhanced by nitrogen doping.Owing to nitrogen doping,atomically dispersed and stable Cu sites resistant to light irradiation are formed on Cu/TiO_(2).The electronic interaction between Cu and nitrogen ions originates valence band structure and defect levels composed of N 2p orbit,distinct from undoped Cu/TiO_(2).Therefore,the lifetime of charge carriers is prolonged,resulting in the pro-duction of C_(1) chemicals and H_(2) with productivities 1.7 and 2.1 folds that of Cu/TiO_(2).This work pro-vides a strategy to design coordinatively stable Cu ions for photocatalytic biomass conversion. 展开更多
关键词 cu photocatalyst coordination structure BIOMASS cc bond c_(1) chemicals
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Synthesis,crystal structures,and antibacterial activities of two zinc(Ⅱ) complexes bearing 5⁃phenyl⁃1H⁃pyrazole group
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作者 LIU Chao WU Jiang JIN Zhaolei 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第10期1986-1994,共9页
A novel compound(H_(2)L)SCN(5⁃methyl⁃3⁃phenyl⁃2H⁃pyrazol⁃1⁃ium thiocyanate)has been obtained by the reaction of thiosemicarbazide with benzoylacetone in ethanol.Two zinccomplexes[Zn(HL)_(2)(NCS)(CH_(3)COO)](1)and[Zn_(... A novel compound(H_(2)L)SCN(5⁃methyl⁃3⁃phenyl⁃2H⁃pyrazol⁃1⁃ium thiocyanate)has been obtained by the reaction of thiosemicarbazide with benzoylacetone in ethanol.Two zinccomplexes[Zn(HL)_(2)(NCS)(CH_(3)COO)](1)and[Zn_(2)(L)_(2)(HL)_(2)(NCS)_(2)]_(2)·2CH_(3)OH(2)have been synthesized by the coordination reactions of Zn(OAc)_(2)·2H_(2)O or ZnCl_(2)with(H_(2)L)SCN under reflux conditions.Elemental analyses and single⁃crystal X⁃ray diffraction have con⁃firmed the structures of the synthesized compounds.The(H_(2)L)SCN ligand and complex 1 pertain to the triclinic sys⁃tem with space group P1,while complex 2 belongs to the monoclinic system with space group P2_(1)/n.Additionally,the antibacterial activities of the compounds were evaluated in vitro using the agar diffusion method against the bac⁃terial strains(Candida albicans,Staphylococcus aureus,and Escherichia coli).The results showed that the ligand exhibited relatively good antibacterial activities against the bacteria,and the complexes possessed stronger antibac⁃terial activities against the same bacteria than the free ligand.CCDC:2190252,(H2L)SCN;2190253,1;2190256,2. 展开更多
关键词 zinccomplex 5⁃phenyl⁃1h⁃pyrazole ThIOcYANATE crystal structure BAcTERIA
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Fine-tuning electronic structure of N-doped graphitic carbon-supported Co-and Fe-incorporated Mo_(2)C to achieve ultrahigh electrochemical water oxidation activity
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作者 Md.Selim Arif Sher Shah Hyeonjung Jung +3 位作者 Vinod K.Paidi Kug-Seung Lee Jeong Woo Han Jong Hyeok Park 《Carbon Energy》 SCIE EI CAS CSCD 2024年第7期134-149,共16页
Mo_(2)C is an excellent electrocatalyst for hydrogen evolution reaction(HER).However,Mo_(2)C is a poor electrocatalyst for oxygen evolution reaction(OER).Herein,two different elements,namely Co and Fe,are incorporated... Mo_(2)C is an excellent electrocatalyst for hydrogen evolution reaction(HER).However,Mo_(2)C is a poor electrocatalyst for oxygen evolution reaction(OER).Herein,two different elements,namely Co and Fe,are incorporated in Mo_(2)C that,therefore,has a finely tuned electronic structure,which is not achievable by incorporation of any one of the metals.Consequently,the resulting electrocatalyst Co_(0.8)Fe_(0.2)-Mo_(2)C-80 displayed excellent OER catalytic performance,which is evidenced by a low overpotential of 214.0(and 246.5)mV to attain a current density of 10(and 50)mA cm^(-2),an ultralow Tafel slope of 38.4 mV dec^(-1),and longterm stability in alkaline medium.Theoretical data demonstrates that Co_(0.8)Fe_(0.2)-Mo_(2)C-80 requires the lowest overpotential(1.00 V)for OER and Co centers to be the active sites.The ultrahigh catalytic performance of the electrocatalyst is attributed to the excellent intrinsic catalytic activity due to high Brunauer-Emmett-Teller specific surface area,large electrochemically active surface area,small Tafel slope,and low chargetransfer resistance. 展开更多
关键词 fine-tuning electronic structures heteronanostructures Mo_(2)c multimetal(co/Fe) oxygen evolution reaction
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Designing Symmetric Gradient Honeycomb Structures with Carbon‑Coated Iron‑Based Composites for High‑Efficiency Microwave Absorption
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作者 Yu Zhang Shu‑Hao Yang +9 位作者 Yue Xin Bo Cai Peng‑Fei Hu Hai‑Yang Dai Chen‑Ming Liang Yun‑Tong Meng Ji‑Hao Su Xiao‑Juan Zhang Min Lu Guang‑Sheng Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期224-241,共18页
The impedance matching of absorbers is a vital factor affecting their microwave absorption(MA)properties.In this work,we controllably synthesized Material of Institute Lavoisier 88C(MIL-88C)with varying aspect ratios(... The impedance matching of absorbers is a vital factor affecting their microwave absorption(MA)properties.In this work,we controllably synthesized Material of Institute Lavoisier 88C(MIL-88C)with varying aspect ratios(AR)as a precursor by regulating oil bath conditions,followed by one-step thermal decomposition to obtain carbon-coated iron-based composites.Modifying the precursor MIL-88C(Fe)preparation conditions,such as the molar ratio between metal ions and organic ligands(M/O),oil bath temperature,and oil bath time,influenced the phases,graphitization degree,and AR of the derivatives,enabling low filler loading,achieving well-matched impedance,and ensuring outstanding MA properties.The MOF-derivatives 2(MD_(2))/polyvinylidene Difluoride(PVDF),MD_(3)/PVDF,and MD4/PVDF absorbers all exhibited excellent MA properties with optimal filler loadings below 20 wt%and as low as 5 wt%.The MD_(2)/PVDF(5 wt%)achieved a maximum effective absorption bandwidth(EAB)of 5.52 GHz(1.90 mm).The MD_(3)/PVDF(10 wt%)possessed a minimum reflection loss(RL_(min))value of−67.4 at 12.56 GHz(2.13 mm).A symmetric gradient honeycomb structure(SGHS)was constructed utilizing the high-frequency structure simulator(HFSS)to further extend the EAB,achieving an EAB of 14.6 GHz and a RL_(min) of−59.0 dB.This research offers a viable inspiration to creating structures or materials with high-efficiency MA properties. 展开更多
关键词 MIL-88c(Fe) Fe/Fe_(3)O_(4)/Fe_(3)c@c controllable preparation Symmetric gradient honeycomb structure Microwave absorbing
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Evaluation of Technical Education by Using a Modern Structured MOODLE Laboratory Course, in Relation to Recent Data
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作者 Gerasimos Vlassopoulos George Albert Karikas +4 位作者 Efstathia Papageorgiou Ioannis Psaromiligkos Niki Giannouli Pigi Vlassopoulou Petros Karkalousos 《Journal of Intelligent Learning Systems and Applications》 2024年第3期316-339,共24页
E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a mo... E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a modern structured MOODLE interactive course, designed for the needs of the laboratory course “Automotive Systems”. The study concerns Greek secondary vocational education pupils aged 18 and vocational training adult students aged 20 to 50 years. The multistage, equal size simple random cluster sample was used as a sampling method. Pupils and adult students of each cluster completed structured 10-question questionnaires both before and after attending the course. A total of 120 questionnaires were collected. In general, our findings disclosed that the majority of pupils and adult students had significantly improved their knowledge and skills from using MOODLE. They reported strengthening conventional teaching, using the new MOODLE technology. The satisfaction indices improved quite, with the differences in their mean values being statistically significant. 展开更多
关键词 Information and communication Technologies (IcT) Distance Learning E-Learning Students’ Opinions Education in Greece I.c.T. in Greece STUDENTS Pupils Adults Adult Students MOODLE MOOc (V.h.S.) Vocational high Schools (S.h.V.T.) Schools of higher Vocational Training VOcATIONAL Profession Interactive Lessons courses Training Laboratory course Secondary Education Automotive Systems car Systems
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Binary molten salt in situ synthesis of sandwich-structure hybrids of hollowβ-Mo2C nanotubes and N-doped carbon nanosheets for hydrogen evolution reaction
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作者 Tianyu Gong Yang Liu +6 位作者 Kai Cui Jiali Xu Linrui Hou Haowen Xu Ruochen Liu Jianlin Deng Changzhou Yuan 《Carbon Energy》 SCIE EI CAS CSCD 2023年第12期111-124,共14页
Focused exploration of earth-abundant and cost-efficient non-noble metal electrocatalysts with superior hydrogen evolution reaction(HER)performance is very important for large-scale and efficient electrolysis of water... Focused exploration of earth-abundant and cost-efficient non-noble metal electrocatalysts with superior hydrogen evolution reaction(HER)performance is very important for large-scale and efficient electrolysis of water.Herein,a sandwich composite structure(designed as MS-Mo2C@NCNS)ofβ-Mo2C hollow nanotubes(HNT)and N-doped carbon nanosheets(NCNS)is designed and prepared using a binary NaCl–KCl molten salt(MS)strategy for HER.The temperature-dominant Kirkendall formation mechanism is tentatively proposed for such a three-dimensional hierarchical framework.Due to its attractive structure and componential synergism,MS-Mo2C@NCNS exposes more effective active sites,confers robust structural stability,and shows significant electrocatalytic activity/stability in HER,with a current density of 10 mA cm-2 and an overpotential of only 98 mV in 1 M KOH.Density functional theory calculations point to the synergistic effect of Mo2C HNT and NCNS,leading to enhanced electronic transport and suitable adsorption free energies of H*(ΔGH*)on the surface of electroactive Mo2C.More significantly,the MS-assisted synthetic methodology here provides an enormous perspective for the commercial development of highly active non-noble metal electrocatalysts toward efficient hydrogen evolution. 展开更多
关键词 binary molten-salt synthesis hydrogen evolution reaction Mo2c hollow nanotubes N-doped carbon nanosheets sandwich structure
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Genetic diversity and population structure of the sea star Asterias amurensis in the northern coast of China
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作者 Quanchao WANG Ying LIU +2 位作者 Zirui PENG Linlin CHEN Baoquan LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1593-1601,共9页
The sea star Asterias amurensis is widely viewed as a severe“marine pest”because of its broad feeding habits.Over the past few decades,A.amurensis undergoes massive and sporadic population outbreaks worldwide,causin... The sea star Asterias amurensis is widely viewed as a severe“marine pest”because of its broad feeding habits.Over the past few decades,A.amurensis undergoes massive and sporadic population outbreaks worldwide,causing extensive economic and ecological losses to the local aquaculture industry and marine ecosystem.Understanding the genetic diversity and population structure of A.amurensis can provide vital information for resource management.By analyzing the polymorphism of the mitochondrial cytochrome C oxidase subunit I(COI)gene and ten simple sequence repeat(SSR)microsatellites markers,the genetic diversity and population structure of A.amurensis of four populations along the northern coast of China was uncovered.A total of 36 haplotypes were identified,and a main haplotype was found in four populations.The Qingdao(QD)population displayed the highest genetic diversity among all the populations.The AMOVA and pairwise F_(st)showed that there was small but statistically significant population differentiation among the four populations,especially between QD and Weihai(WH).Moreover,the principal component analysis(PCA)and admixture analysis showed that several individuals in Yantai(YT)and Dalian(DL)had little genetic association with other individuals.Overall,this study provided useful information of the genetic diversity and population structure of A.amurensis and will contribute to the resource management of A.amurensis in China. 展开更多
关键词 Asterias amurensis cytochrome c oxidase subunit I(cOI) simple sequence repeat(SSR) population structure china seas
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可见光诱导6H-苯并[c]苯并吡喃及二氢菲啶衍生物的合成
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作者 杨森 胡浩 陈铭 《常州大学学报(自然科学版)》 CAS 2024年第4期1-7,共7页
开发出了可见光诱导的分子内C—H芳基化反应,合成了一系列6H-苯并[c]苯并吡喃及二氢菲啶衍生物。合成得到的产物用^(1)H NMR以及^(13)C NMR进行结构表征。与传统方法相比,该方法利用清洁可再生的光能驱动化学反应,避免了高温、高压等严... 开发出了可见光诱导的分子内C—H芳基化反应,合成了一系列6H-苯并[c]苯并吡喃及二氢菲啶衍生物。合成得到的产物用^(1)H NMR以及^(13)C NMR进行结构表征。与传统方法相比,该方法利用清洁可再生的光能驱动化学反应,避免了高温、高压等严格的反应条件。此外,该方法具有原料易得、底物适用范围广泛、反应条件温和、操作简单等优点。 展开更多
关键词 可见光诱导 c—h芳基化 6h-苯并[c]苯并吡喃 二氢菲啶 杂环化合物
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The Inner Structure of the Intrinsic Electron and the Origin of Self-Mass
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作者 Victor Vaguine 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期174-189,共16页
A brief review and analysis of two historical models of the electron, the charged spinning sphere and Goudsmit and Uhlenbeck’s concept, is presented. It is shown that the enormous potential of classical electrodynami... A brief review and analysis of two historical models of the electron, the charged spinning sphere and Goudsmit and Uhlenbeck’s concept, is presented. It is shown that the enormous potential of classical electrodynamics has been underutilized in particle physics. Such observation leads to discovery of a principal component in the electron inner structure—the charged c-ring. The intrinsic (fundamental) electron model based on the charged c-ring successfully explains the ontology of the charge fractionation in quantum chromodynamics and the formation of Cooper pairs in superconductivity. The c-ring properties are explained on the basis of the General Compton Conditions as defined. Properties of the charged c-ring include the explanation of the boundary conditions, electro-magnetostatic field configuration, self-mass, spin, magnetic moment, and the gyromagnetic ratio. The self-mass of the intrinsic electron is 100% electro-magnetostatic and it is shown how to compute its value. The classical-quantum divide no longer exists. Relation between the intrinsic electron and the electron is fundamentally defined. The electron is the composite fermion consisting of the intrinsic electron and the neutrino. The ontology of the anomaly in the electron magnetic moment is demonstrated—it is due to the addition of the neutrino magnetic moment to the overall electron magnetic moment. The intrinsic electron replaces the W? boson in particle physics, resulting in a fundamental implication for the Standard Model. 展开更多
关键词 Intrinsic Electron Inner structure Electro-Magnetostatic Self-Mass General compton conditions charged c-Ring Visualization c-Ring Length constant
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五味子乙素预处理对过氧化氢诱导的H9c2细胞焦亡及TXNIP/NLRP3/Caspase-1通路的影响
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作者 王瑞婷 赵松 +2 位作者 郝娜 李立萍 解丽君 《现代中西医结合杂志》 CAS 2024年第13期1807-1812,共6页
目的基于硫氧还蛋白互作蛋白(TXNIP)/核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)/半胱氨酸蛋白酶-1(Caspase-1)通路观察五味子乙素对过氧化氢(H 2O 2)诱导的大鼠H9c2心肌细胞氧化损伤及焦亡的影响,探讨五味子乙素的心肌保护作用机制。... 目的基于硫氧还蛋白互作蛋白(TXNIP)/核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)/半胱氨酸蛋白酶-1(Caspase-1)通路观察五味子乙素对过氧化氢(H 2O 2)诱导的大鼠H9c2心肌细胞氧化损伤及焦亡的影响,探讨五味子乙素的心肌保护作用机制。方法体外培养H9c2心肌细胞,实验设4组:正常组细胞常规孵育,五味子乙素组细胞加入40μmol/L五味子乙素孵育24 h,H 2O 2组细胞加入1000μmol/L的H 2O 2孵育30 min,H 2O 2+五味子乙素组细胞加入40μmol/L五味子乙素孵育24 h后再加入H 2O 2孵育30 min。CCK-8法检测细胞活力,DCFH-DA探针检测细胞中活性氧(ROS)含量,试剂盒检测细胞培养上清中乳酸脱氢酶(LDH)含量和细胞中丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)含量,Western blot法检测细胞中TXNIP、硫氧还蛋白(Trx)、NLRP3、裂解的半胱氨酸蛋白酶-1(Cleaved Caspase-1)、消皮素D(GSDMD)-N蛋白表达情况,ELISA法检测细胞培养上清中白细胞介素-18(IL-18)、白细胞介素-1β(IL-1β)含量。结果与正常组比较,H 2O 2组细胞活力明显下降(P<0.05),细胞中ROS、MDA含量和TXNIP、NLRP3、Cleaved Caspase-1、GSDMD-N蛋白相对表达量及细胞培养上清中LDH、IL-1β、IL-18含量均明显升高(P均<0.05),细胞中SOD、GSH-Px含量和Trx蛋白相对表达量均明显降低(P均<0.05);与H 2O 2组比较,H 2O 2+五味子乙素组的细胞活力明显升高(P<0.05),细胞中ROS、MDA含量和TXNIP、NLRP3、Cleaved Caspase-1、GSDMD-N蛋白相对表达量及细胞培养上清中LDH、IL-1β、IL-18含量均明显降低(P均<0.05),细胞中SOD、GSH-Px含量和Trx蛋白相对表达量均明显升高(P均<0.05)。结论五味子乙素可能通过影响TXNIP/NLRP3/Caspase-1通路,从而减轻H 2O 2诱导的H9c2细胞氧化损伤,抑制心肌细胞焦亡。 展开更多
关键词 五味子乙素 h9c2 氧化应激 焦亡 硫氧还蛋白互作蛋白 核苷酸结合寡聚化结构域样受体蛋白3
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纳米C-S-H/PCE对蒸养UHPC力学性能增强机理研究
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作者 伍勇华 易昂 +2 位作者 何娟 匡玉峰 原毅冰 《硅酸盐通报》 CAS 北大核心 2024年第8期2797-2805,共9页
目前超高性能混凝土(UHPC)制品的力学性能有待进一步提升,采用纳米C-S-H/PCE对UHPC进行增强在理论上是一种可行的技术途径。本文研究了蒸养条件下掺入以聚羧酸(PCE)为分散剂的纳米水化硅酸钙(C-S-H/PCE)对UHPC力学性能的影响,通过测试... 目前超高性能混凝土(UHPC)制品的力学性能有待进一步提升,采用纳米C-S-H/PCE对UHPC进行增强在理论上是一种可行的技术途径。本文研究了蒸养条件下掺入以聚羧酸(PCE)为分散剂的纳米水化硅酸钙(C-S-H/PCE)对UHPC力学性能的影响,通过测试水化热、水化产物、微观形貌和孔结构等对其机理进行了分析。结果表明,掺入3.0%(质量分数)纳米C-S-H/PCE可以显著提高蒸养UHPC的抗压强度和抗折强度。掺入纳米C-S-H/PCE可以促进UHPC的早期水化,生成更多的水化硅酸钙(C-S-H)凝胶,使水化放热温峰增高,并缩短达到水化温峰的时间。掺入纳米C-S-H/PCE可有效改善蒸养UHPC的孔结构,在掺量为3.0%(质量分数)时总孔隙率最小,有害孔比例最低。该研究可为纳米C-S-H/PCE在蒸养UHPC中的应用提供参考。 展开更多
关键词 纳米c-S-h/PcE 超高性能混凝土 孔结构 水化放热 蒸汽养护
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IGF-1介导MAPKs通路在C3H10T1/2细胞成骨分化中的作用
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作者 李冬 董晓俊 徐成栋 《中国骨质疏松杂志》 CAS CSCD 北大核心 2024年第5期668-672,共5页
目的探究胰岛素样生长因子1(IGF-1)介导丝裂原活化蛋白激酶(MAPKs)信号通路在C3H10T1/2细胞成骨分化中的调控作用及机制。方法不同浓度IGF-1(0、5、10、20 ng/mL)培养C3H10T1/2细胞,碱性磷酸酶(ALP)与茜素红(ARS)染色检测ALP活性、钙盐... 目的探究胰岛素样生长因子1(IGF-1)介导丝裂原活化蛋白激酶(MAPKs)信号通路在C3H10T1/2细胞成骨分化中的调控作用及机制。方法不同浓度IGF-1(0、5、10、20 ng/mL)培养C3H10T1/2细胞,碱性磷酸酶(ALP)与茜素红(ARS)染色检测ALP活性、钙盐沉积情况,qRT-PCR法检测成骨特性因子核心结合因子α-1(RUNX2)、成骨分化特异性因子骨桥蛋白(OPN)、骨钙蛋白(OCN)mRNA表达水平,Western Blot法检测MAPK通路蛋白磷酸化表达水平。对数期细胞分为空白组、IGF-1组、ERK通路抑制剂(PD98059)组、PD+IGF-1组、p38通路抑制剂(SB202192)组、SB+IGF-1组,qRT-PCR法检测成骨特性因子RUNX2、成骨分化特异性因子骨桥蛋白(OPN)、骨钙蛋白(OCN)mRNA表达水平。结果不同浓度IGF-1组ALP显色加深,ALP活性升高,钙盐结节形成增多,RUNX2、OPN、OCN mRNA表达水平升高,磷酸化ERK、p38、JNK蛋白表达增加,具有剂量效应(P<0.05)。与空白组比较,PD组、SB组C3H10T1/2细胞RUNX2、OPN、OCN mRNA表达水平明显降低(P<0.05),PD+IGF-1组、SB+IGF-1组C3H10T1/2细胞RUNX2、OPN、OCN mRNA表达水平明显升高(P<0.05);但与IGF-1组比较,PD+IGF-1组、SB+IGF-1组C3H10T1/2细胞RUNX2、OPN、OCN mRNA表达水平明显降低(P<0.05)。结论IGF-1促进C3H10T1/2细胞成骨分化,其作用机制可能与激活ERK信号通路和p38 MAPK信号通路有关。 展开更多
关键词 胰岛素样生长因子1 丝裂原活化蛋白激酶信号通路 c3h10T1/2细胞 成骨分化
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H Control for Externally Excited Building Structures with Active Mass Damper under Actuator Saturation
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作者 Shulong Wei Yuanguang Zheng 《Open Journal of Applied Sciences》 2023年第11期1951-1966,共16页
This paper investigates the application of active mass dampers to mitigate the vibrations of building structures subjected to unknown external excitations under controller saturation conditions. By utilizing an H<s... This paper investigates the application of active mass dampers to mitigate the vibrations of building structures subjected to unknown external excitations under controller saturation conditions. By utilizing an H<sub>∞</sub> control strategy, the optimal state feedback controller is derived by solving the linear matrix inequality problem for controller saturation. Case studies show that the proposed controller is capable of stabilizing the closed-loop system with good control performance and effectively suppressing vibrations in building structures under unknown external excitation. When compared to controllers that do not consider saturation, the proposed controller requires lower gain and results in reduced energy consumption. The research findings provide valuable insights for addressing real-world building structure control problems, contributing to both theoretical significance and practical applications. 展开更多
关键词 structural Vibration Active Mass Damper h control controller Saturation Linear Matrix Inequality
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基于AMPK/mTOR通路探讨注射用益气复脉对TBHP诱导H9c2细胞损伤的保护作用
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作者 王瑜 苗婷 马胜男 《中国中医药科技》 CAS 2024年第4期602-606,共5页
目的:探讨注射用益气复脉(YQFM)通过AMPK/mTOR信号通路调控自噬减轻叔丁基过氧化氢(TBHP)所致H9c2心肌细胞损伤的机制。方法:体外培养H9c2心肌细胞,分为正常对照组、TBHP组、TBHP+YQFM组。CCK-8法检测各组H9c2心肌细胞存活率;免疫荧光... 目的:探讨注射用益气复脉(YQFM)通过AMPK/mTOR信号通路调控自噬减轻叔丁基过氧化氢(TBHP)所致H9c2心肌细胞损伤的机制。方法:体外培养H9c2心肌细胞,分为正常对照组、TBHP组、TBHP+YQFM组。CCK-8法检测各组H9c2心肌细胞存活率;免疫荧光检测细胞自噬情况;免疫印迹法检测各组细胞自噬相关蛋白LC3Ⅱ/LC3Ⅰ及AMPK/mTOR通路相关蛋白表达。结果:用2、4、8、16 g/L的YQFM预处理后,可显著恢复TBHP诱导的H9c2细胞损伤;免疫荧光染色结果显示,与正常对照组相比,TBHP组细胞LC3荧光强度显著升高(P<0.01);与TBHP组相比,TBHP+YQFM组LC3荧光强度降低,其中2 g/L YQFM组具有显著性(P<0.05)。Western blot检测结果显示:TBHP组p-AMPK/AMPK、LC3-Ⅱ/LC3-Ⅰ表达显著增加,p-mTOR/mTOR比率显著降低;YQFM预处理使自噬相关蛋白p-AMPK/AMPK、LC3-Ⅱ/LC3-Ⅰ比率明显降低,4 g/L YQFM组p-mTOR/mTOR比率明显升高。结论:注射用益气复脉能有效拮抗TBHP引起的H9c2细胞损伤,其机制与通过AMPK/mTOR信号通路调控自噬途径有关。 展开更多
关键词 注射用益气复脉 叔丁基过氧化氢 h9c2心肌细胞 AMPK/mTOR信号通路 自噬 体外实验
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The Intrinsic Electron with Its Properties Such as Inner Structure and Self-Mass Is in Conflict with Quantum Field Theory
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作者 Victor Vaguine 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第3期583-595,共13页
The quantum field theory (QFT) is one of branches of the Standard Model. According to QFT, quantum fields are the primary entities and particles are the excitations of these fields, coming in discrete lumps with no in... The quantum field theory (QFT) is one of branches of the Standard Model. According to QFT, quantum fields are the primary entities and particles are the excitations of these fields, coming in discrete lumps with no inner structures and with properties assigned by declaration. Such view is in conflict with the observed vacuum energy density, 140 orders of magnitudes less than required by the QFT. In addition, such view is challenged by Aphysical Quantum Mechanics (AQM), a deeper quantum theory. According to AQM, the fundamental understanding of quantum reality is expanded by the addition of two fundamental categories, aphysical and elementary consciousness of elementary particles. Based on AQM and as an example, the total ontology of the intrinsic (fundamental) electron is presented with its inner structure of perfect geometry consisting of the physical charged c-ring and aphysical cylinder, and with its properties such as self-mass, spin, magneto-electrostatic field configuration and magnetic moment. The position parameter in the inner structure demonstrates that there are no two identical intrinsic electrons in the Universe thus placing a question mark over the QFT principle of indistinguishability. 展开更多
关键词 Quantum Reality Physical-Aphysical Intrinsic Electron charged c-Ring Aphysical cylinder Elementary consciousness Position Parameter constant U Ontology Self-Mass Indistinguishable Inner structure
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氯自由基介导的光催化芳基醚C(sp^(3))−H氧化生成酯
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作者 刘玉庭 聂贝黎 +2 位作者 李宁 刘慧芳 王峰 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第3期123-128,共6页
饱和的碳氢键氧化是合成化学和化学工业中一类重要的化学反应.然而,饱和C(sp^(3))−H键离解能(BDEs)较高、极性较弱,导致了底物难以活化和催化转化效率较低等问题.在过去的几十年,C(sp^(3))−H键的定向活化转化取得了重要的进展.其中,关于... 饱和的碳氢键氧化是合成化学和化学工业中一类重要的化学反应.然而,饱和C(sp^(3))−H键离解能(BDEs)较高、极性较弱,导致了底物难以活化和催化转化效率较低等问题.在过去的几十年,C(sp^(3))−H键的定向活化转化取得了重要的进展.其中,关于C(sp^(3))−H键催化氧化的研究主要涉及一些键能低的、预活化的C−H键,包括苄基型、亚甲基型、脂肪族X−CH_(2)(X=O,N)和甲苯等,含有未活化C(sp^(3))−H键的复杂化合物的选择性氧化仍具有挑战性.例如,芳基醚C(sp^(3))−H键功能化通常采用计量的过氧化物氧化剂,或者通过单电子氧化和碱促进的去质子化进一步构建C−C/C−N键,产物选择性较低,也带来了一些不利的环境影响.因此,有必要开发高效、温和的芳基醚C(sp^(3))−H键选择氧化方法,并将其应用于有机合成和药物开发.近年来,光催化C(sp^(3))−H键氧化因其操作简便、氧化还原中性等优点,已发展成为一种有用且多样的催化研究工具.本文发展了一种利用氧气作为氧化剂,在可见光驱动下选择性地将芳基醚C(sp^(3))−H键氧化成为甲酸苯酯类产物的新方法.使用Mes-10-phenyl-Acr^(+)−BF_(4)^(-)光催化剂,高效活化多种氯源(如盐酸、无机氯盐和有机氯化物)得到氯自由基,由于其具有较高的氧化能力(+2.03 V vs.SCE)和对氢原子的亲和力,能够通过氢原子转移过程活化芳基醚C(sp^(3))−键,攫取氢自由基得到相应的烷基碳自由基(•CH_(2)OPh)中间体,进一步被分子氧选择氧化得到酯类目标产物.研究结果表明,多种链状芳基醚和不同取代(如给电子基和吸电子基)芳基醚均可发生氧化反应,高收率地合成了一系列官能团丰富的甲酸苯酯类化合物.本文方法具有反应条件温和、操作简单、官能团耐受性好以及可规模化放大等优点,并且少量的水对反应没有明显影响.机理实验研究结果表明,芳基醚C(sp^(3))−H键的断裂是反应过程的决速步骤.紫外可见吸收光谱结果表明,氯离子与催化剂之间的相互作用强于底物,并且自由基捕获实验证实反应体系中存在氯自由基和烷基碳自由基物种,表明反应经历自由基路径.此外,电子顺磁共振测试结果表明,反应过程中存在单线态氧物种,可能是激发态的光催化剂直接与氧气发生能量转移得到;同位素实验(18O)揭示了甲酸苯酯类化合物氧的来源.综上,本文实现了温和条件下光催化芳基醚C(sp^(3))−H键选择氧化反应,高收率合成了一系列甲酸苯酯类化合物.该方法避免了化学计量的过氧化物和碱等添加剂的使用以及底物的过度氧化,阐明了催化反应机制,为其他醚类化合物的C(sp^(3))−H键氧化功能化提供了新思路,为后续化学合成和药物开发提供了参考和启示. 展开更多
关键词 氯自由基 光催化 c(sp^(3))−h 催化氧化 芳基醚
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10℃条件下纳米C-S-H掺量对水泥早期水化的影响 被引量:1
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作者 房延凤 惠一心 +2 位作者 尚小朋 丁向群 佟钰 《沈阳建筑大学学报(自然科学版)》 CAS 北大核心 2024年第3期505-512,共8页
目的探究10℃条件下不同掺量纳米C-S-H对水泥早期水化进程及强度发展的影响,并分析其早强剂作用机理。方法通过溶液共沉淀法制备纳米C-S-H悬浮液,将其掺入到普通硅酸盐水泥中,在10℃条件下进行养护,分析其对水泥凝结时间、抗折强度、抗... 目的探究10℃条件下不同掺量纳米C-S-H对水泥早期水化进程及强度发展的影响,并分析其早强剂作用机理。方法通过溶液共沉淀法制备纳米C-S-H悬浮液,将其掺入到普通硅酸盐水泥中,在10℃条件下进行养护,分析其对水泥凝结时间、抗折强度、抗压强度的影响;通过XRD、TG等检测手段分析水泥的水化进程及对水化产物的影响。结果掺入0.05%纳米C-S-H,可使水泥初凝时间缩短9.9%,终凝时间缩短10.4%;24 h时抗折强度和抗压强度分别提高了34%和33.5%。纳米C-S-H的掺入造成水泥3 d抗折强度略有降低。水化产物中Ca(OH)2质量分数在12 h、16 h和24 h时较参比样分别提高了17.6%、21.3%和29.6%。结论在10℃条件下,纳米C-S-H的加入能够有效促进C 3S和C 2S的水化过程,形成更多的水化产物,从而缩短水泥凝结时间,提高24 h内水泥砂浆强度,28 d强度没有显著降低。 展开更多
关键词 纳米c-S-h 稳定性 10℃ 早期水化 抗压强度
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C/O与C/H测井响应的数值模拟对比研究
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作者 李巽 吴文圣 董夺 《核技术》 EI CAS CSCD 北大核心 2024年第4期90-96,共7页
准确地测定地层中含油饱和度是储层岩石物理评价的重要组成部分,C/H测井和C/O测井都是计算低矿化度储层含油饱和度的主要方法。为了对比C/H与C/O两种方法的测井响应效果,采用蒙特卡罗模拟方法,应用球状模型和参考Halliburton公司的C/O... 准确地测定地层中含油饱和度是储层岩石物理评价的重要组成部分,C/H测井和C/O测井都是计算低矿化度储层含油饱和度的主要方法。为了对比C/H与C/O两种方法的测井响应效果,采用蒙特卡罗模拟方法,应用球状模型和参考Halliburton公司的C/O测井仪器储层性能检测仪(Reservoir Performance Monitor,RPM)所设置的模型进行数值模拟。计算得到了不同地质参数和孔隙结构下地层原子特征能窗的γ光子计数,分析了C/O和C/H与孔隙度和饱和度的关系以及对饱和度的灵敏度。计算结果表明:在套管井中C/H和C/O与孔隙度和饱和度具有相同的关系,都可以用于井下的饱和度计算。但是C/H受井眼环境影响更大,对饱和度的灵敏度更低,不适用于复杂井眼的饱和度计算。 展开更多
关键词 c/O测井 c/h测井 测井响应 计算模型
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天麻降压胶囊治疗H型高血压肝火亢盛证的临床效果及对同型半胱氨酸、超敏C反应蛋白的影响
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作者 曹宝国 刘惠娟 +2 位作者 樊红波 陈圆圆 秦少华 《中国当代医药》 CAS 2024年第19期95-100,共6页
目的观察天麻降压胶囊治疗H型高血压(肝火亢盛证)的临床效果及对同型半胱氨酸(Hcy)、超敏C反应蛋白(hs-CRP)的影响。方法选取2021年5月至2022年12月天水市中医医院就诊的165例轻、中度H型高血压(肝火亢盛证)患者作为研究对象,按照随机... 目的观察天麻降压胶囊治疗H型高血压(肝火亢盛证)的临床效果及对同型半胱氨酸(Hcy)、超敏C反应蛋白(hs-CRP)的影响。方法选取2021年5月至2022年12月天水市中医医院就诊的165例轻、中度H型高血压(肝火亢盛证)患者作为研究对象,按照随机数字表法将其分为对照组(83例)和治疗组(82例)。对照组予以马来酸依那普利叶酸片治疗,治疗组在对照组基础上加服天麻降压胶囊治疗,两组均治疗3个月。比较治疗前后两组患者的收缩压、舒张压、Hcy、hs-CRP水平及中医证候积分的情况,并判断血压疗效及中医疗效。结果治疗后,两组患者的收缩压与舒张压均低于本组治疗前,且治疗组的收缩压与舒张压均低于对照组,差异有统计学意义(P<0.05);治疗组的血压总有效率(97.56%)高于对照组(86.75%),差异有统计学意义(P<0.05)。治疗后,两组患者的Hcy、hs-CRP水平及中医证候总积分均低于本组治疗前,且治疗组的Hcy、hs-CRP水平及中医证候总积分均低于对照组,差异有统计学意义(P<0.05);治疗组的中医治疗总有效率(85.37%)高于对照组(73.49%),差异有统计学意义(P<0.05)。结论天麻降压胶囊治疗H型高血压(肝火亢盛证)具有较好的临床疗效,可显著改善患者症状,降低Hcy、hs-CRP水平,值得进一步推广应用。 展开更多
关键词 h型高血压 肝火亢盛证 天麻降压胶囊 同型半胱氨酸 超敏c反应蛋白
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TP53-R273H/R273C基因突变数字PCR检测方法研究
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作者 张洁洁 牛春艳 +2 位作者 王霞 杨靖亚 董莲华 《计量学报》 CSCD 北大核心 2024年第8期1242-1248,共7页
TP53基因是肿瘤的抑制基因,也是癌症中常用的靶向检测基因。R273H和R273C是TP53基因检测中常见的热点突变。为了建立这2个突变的微滴式数字聚合酶链式反应(ddPCR)检测方法,针对突变位点分别设计了2套ddPCR方法,验证了探针的特异性,并对... TP53基因是肿瘤的抑制基因,也是癌症中常用的靶向检测基因。R273H和R273C是TP53基因检测中常见的热点突变。为了建立这2个突变的微滴式数字聚合酶链式反应(ddPCR)检测方法,针对突变位点分别设计了2套ddPCR方法,验证了探针的特异性,并对退火温度和引物探针浓度进行了优化。结果显示,所建立的方法具有良好的特异性和重复性,ddPCR法与重量法之间的相关系数为0.9997和0.9996。R273H和R273C的检出限均为0.02%,定量限均为0.05%。这2套方法可用于准确检测TP53-R273H和TP53-R273C基因突变,为临床应用提供支持。 展开更多
关键词 生物计量 TP53 基因突变 R273h R273c 核酸检测 数字PcR
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