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Positive Q-Value Neutron Transfer Mediated Sub-Barrier Fusion Reactions
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作者 Pei-Wei Wen Zhao-Qing Feng +3 位作者 Fan Zhang Cheng Li Cheng-aian Li Feng-Shou Zhang 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第4期22-25,共4页
Positive Q-value neutron transfer mediated sub-barrier fusion reactions are studied with an empirical coupled channels model, which takes into account neutron rearrangement related only to the dynamical matching condi... Positive Q-value neutron transfer mediated sub-barrier fusion reactions are studied with an empirical coupled channels model, which takes into account neutron rearrangement related only to the dynamical matching condition with no free parameters. Fusion cross sections of collision systems ^32S+^90,94,96Zr are calculated and analyzed. Logarithmic residual enhancement (LRE) is proposed to evaluate the discrepancy between calculated results and experimental data. The experimental data can be described well with this model for the first time as a whole, while the LRE analysis shows that there are still theoretical systematic deviations. 展开更多
关键词 LRE MRE exp positive Q-Value Neutron Transfer Mediated Sub-Barrier Fusion reactions Zr
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Identification of the starting reaction position in the hydrogenation of (N-ethyl)carbazole over Raney-Ni 被引量:6
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作者 Feifei Sun Yue An +3 位作者 Lecheng Lei Fuying Wu Jingke Zhu Xingwang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第2期219-224,共6页
Hydrogenation of carbazole and N-ethylcarbazole over Raney-Ni catalyst were realized in the temperature range of 393-503 K. 4[H] adduct dominated the hydrogenation products and the formation of 2[H] adduct was the rat... Hydrogenation of carbazole and N-ethylcarbazole over Raney-Ni catalyst were realized in the temperature range of 393-503 K. 4[H] adduct dominated the hydrogenation products and the formation of 2[H] adduct was the rate-limiting step during the period, in which the conversion of carbazole was less than 40%. The hydrogenation process followed pseudo-first-order kinetics and the hydrogenation activation energies of carbazole and N-ethylcarbazole were 90 kJ/mol and 115 kJ/mol, respectively. The reaction starting position as well as the pathway of the hydrogenation of (N-ethyl)carbazole were investigated by comparing the kinetic characteristics of hydrogen uptake of carbazole and N- ethylcarbazole. The results showed that the reaction was a stepwise hydrogenation process and the first H_2 was added to the C1 = C10 double bond in the hydrogenation. 展开更多
关键词 (N-ethyl)carbazole hydrogen storage Raney-Ni catalyst reaction kinetics first reaction position
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Effect of High Positive Acceleration(+Gz) Environment on Dental Implant Osseointegration:A Preliminary Animal Study 被引量:2
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作者 ZHU Xiao Ru DENG Tian Zheng +2 位作者 PANG Jian Liang LIU Bing KE Jie 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2019年第9期687-698,共12页
Objective To observe the effect of high positive acceleration(+Gz) environment on dental implant osseointegration in a rabbit model and to investigate its mechanism.Methods Forty-eight New Zealand white rabbits were r... Objective To observe the effect of high positive acceleration(+Gz) environment on dental implant osseointegration in a rabbit model and to investigate its mechanism.Methods Forty-eight New Zealand white rabbits were randomly divided into 6 groups. The rabbit’s mandibular incisors were extracted and 1 implant was placed in each socket immediately. After 1 week of rest, the rabbits were exposed to a high +Gz environment, 3 times a week. The rabbits were sacrificed at 3 weeks(2 weeks +Gz exposure), 5 weeks(4 weeks +Gz exposure), and 12 weeks(4 weeks +Gz exposure and 7 weeks normal environment) after surgery, respectively. Specimens were harvested for micro-CT scanning, histological analysis, and real-time polymerase chain reaction examination.Results Compared with those in the control group, the mRNA expression levels of bone morphogenetic protein-2(BMP-2), osteopontin(OPN), and transforming growth factor-β1(TGF-β1)were significantly lower(P < 0.05), while the mRNA expression level of receptor activator of nuclear factor κB ligand(RANKL) and the RANKL/osteoprotegerin(OPG) ratio were significantly higher(P < 0.05)at 3 weeks;values of bone volume fraction, trabecular number, bone-implant contact(BIC), and TGF-β1 and OPG mRNA expression levels were significantly lower(P < 0.05), and the value of trabecular separation, RANKL mRNA expression level and RANKL/OPG ratio were significantly higher(P < 0.05) at 5 weeks;and the value of BIC was still significantly lower(P < 0.05) at 12 weeks in the experimental group.Conclusion Early exposure to the high +Gz environment after implant surgery might have an adverse effect on osseointegration, and its mechanism could be related to the inhibition of osteoblast activity and promotion of osteoclast activity. 展开更多
关键词 positive acceleration OSSEOINTEGRATION Dental IMPLANT MICRO-CT Real-time POLYMERASE chain reaction OSTEOBLAST
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EXISTENCE OF THE MINIMAL POSITIVE SOLUTION OF SOME NONLINEAR ELLIPTIC SYSTEMS WHEN THE NONLINEARITY IS THE SUM OF A SUBLINEAR AND A SUPERLINEAR TERM 被引量:2
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作者 Nicolae Tarfulea (Department of Mathematics, the Pennsylvania State University, University Park, PA 16802, U S A) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第3期283-290,共8页
It is shown that there exists Λ>0 such that, for every λ∈(0,Λ), the semilinear elliptic system: - Δ u=λu|u| q-1 +u|u| p-1 -v inΩ, - Δ v=δu-γv in Ω, u=v=0 on Ω, where Ω∈R N(N≥2) is ... It is shown that there exists Λ>0 such that, for every λ∈(0,Λ), the semilinear elliptic system: - Δ u=λu|u| q-1 +u|u| p-1 -v inΩ, - Δ v=δu-γv in Ω, u=v=0 on Ω, where Ω∈R N(N≥2) is a bounded domain with smooth boundary and 0<q<1<p,has a minimal positive solution (u λ,v λ). Moreover: u λ and v λ are strictly increasing with respect to λ. 展开更多
关键词 reaction diffusion system positive solution nonlinear equation
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Different positive end expiratory pressure and tidal volume controls on lung protection and inflammatory factors during surgical anesthesia 被引量:2
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作者 Yu Wang Yi Yang +5 位作者 Ding-Mu Wang Jie Li Quan-Tang Bao Bei-Bei Wang Shu-Jun Zhu Lu Zou 《World Journal of Clinical Cases》 SCIE 2022年第33期12146-12155,共10页
BACKGROUND Mechanical ventilation can lead to the severe impairment of the metabolic pathway of alveolar surfactants,inactivating alveolar surfactants and significantly reducing lung-chest compliance.The cardiopulmona... BACKGROUND Mechanical ventilation can lead to the severe impairment of the metabolic pathway of alveolar surfactants,inactivating alveolar surfactants and significantly reducing lung-chest compliance.The cardiopulmonary function of elderly patients usually reduced to a certain extent,and there are lung complications after surgical anesthesia,just like lung barotrauma caused by mechanical ventilation,atelectasis and postoperative hypoxemia.AIM To investigate the effects of different positive end expiratory pressures(PEEPs)and tidal volumes(VTs)on respiratory function,the degree of the inflammatory response and hemodynamic indexes in patients undergoing surgery under general anesthesia.METHODS A total of 120 patients undergoing surgery for gastric or colon cancer under general anesthesia in Xinghua People's Hospital from January 2017 to January 2021 were randomly divided into Group A and Group B,with 60 cases in each group.The ventilation mode in Group A was VT(6.0 mL/kg)+PEEP(5.0 cmH_(2)O),while that in Group B was VT(6.0 mL/kg)+PEEP(8.0 cmH_(2)O).Blood gas parameters,respiratory mechanical parameters,inflammatory response indicators,hemodynamic indicators and related complications were compared between the two groups.RESULTS There were no significant differences in PaCO_(2),PaO_(2),oxygen or the examined indexes at T0 between group A and group B(P>0.05).The measured PaO_(2) value of patients in group A at T3 was higher than that in group B,and the difference was significant(P<0.05).There were no significant differences in peak airway pressure(P_(peak)),mean airway pressure or dynamic pulmonary compliance(Cdyn)at T0 between group A and group B(P>0.05).The measured P_(peak) value of patients in group A at T1 was higher than that in group B,and the difference was significant(P<0.05).The measured Cdyn value at T1 and T2 was greater than that in group B(P<0.05).Before surgery,there were no significant differences in tumor necrosis factor-α(TNF-α),interleukin(IL)-6 or IL-10 between group A and group B(P>0.05).After 4 h,the measured values of TNF-αand IL-6 in group A were lower than those in group B,and the differences were significant(P<0.05).The IL-10 Level in group A was higher than that in group B(P<0.05).At T0,there were no significant differences in cardiac output,cardiac index(CI),stroke volume index(SVI)or mean arterial pressure between group A and group B(P>0.05).The measured values of CI and SVI at T2 in patients in group A were higher than those in group B,and the differences were significant(P<0.05).CONCLUSION For patients undergoing surgery for gastric or colon cancer under general anesthesia,the VT(6.0 mL/kg)+PEEP(5.0 cmH_(2)O)regimen was more effective than the VT(6.0 mL/kg)+PEEP(8.0 cmH_(2)O)regimen in protecting the lung function and ventilatory function of patients,and it had better effects on maintaining hemodynamic stability and reducing inflammatory reactions. 展开更多
关键词 General anesthesia positive end expiratory pressure Tidal volume Respiratory function Inflammatory reactions HEMODYNAMICS
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Positivity-Preserving Numerical Methods for Belousov-Zhabotinsky Reaction
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作者 Yuro Adachi Novrianti Okihiro Sawada 《Applied Mathematics》 2020年第10期943-950,共8页
The existence of positive solutions to the system of ordinary differential equations related to the Belousov-Zhabotinsky reaction is established. The key idea is to use a new successive approximation of solutions, ens... The existence of positive solutions to the system of ordinary differential equations related to the Belousov-Zhabotinsky reaction is established. The key idea is to use a new successive approximation of solutions, ensuring its positivity. To obtain the positivity and invariant region for numerical solutions, the system is discretized as difference equations of explicit form, employing operator splitting methods with linear stability conditions. Algorithm to solve the alternate solution is given. 展开更多
关键词 positive Solution Difference Equation Belousov-Zhabotinsky reaction Invariant Region Maximum Principle
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Modeling and Analysis of Novel Integrated Radial Hybrid Magnetic Bearing for Magnetic Bearing Reaction Wheel 被引量:8
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作者 HAN Bangcheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第5期655-662,共8页
Conventional ball bearing reaction wheel used to control the attitude of spacecraft can't absorb the centrifugal force caused by imbalance of the wheel rotor,and there will be a torque spike at zero speed,which serio... Conventional ball bearing reaction wheel used to control the attitude of spacecraft can't absorb the centrifugal force caused by imbalance of the wheel rotor,and there will be a torque spike at zero speed,which seriously influences the accuracy and stability of spacecraft attitude control.Compared with traditional ball-bearing wheel,noncontact and no lubrication are the remarkable features of the magnetic bearing reaction wheel,and which can solve the high precision problems of wheel.In general,two radial magnetic bearings are needed in magnetic bearing wheel,and the design results in a relatively large axial dimension and smaller momentum-to-mass ratios.In this paper,a new type of magnetic bearing reaction wheel(MBRW) is introduced for satellite attitude control,and a novel integrated radial hybrid magnetic bearing(RHMB) with permanent magnet bias is designed to reduce the mass and minimize the size of the MBRW,etc.The equivalent magnetic circuit model for the RHMB is presented and a solution is found.The stiffness model is also presented,including current stiffness,position negative stiffness,as well as tilting current stiffness,tilting angular position negative stiffness,force and moment equilibrium equations.The design parameters of the RHMB are given according to the requirement of the MBRW with angular momentum of 30 N ? m ? s when the rotation speed of rotor reaches to 5 kr/min.The nonlinearity of the RHMB is shown by using the characteristic curves of force-control current-position,current stiffness,position stiffness,moment-control current-angular displacement,tilting current stiffness and tilting angular position stiffness considering all the rotor position within the clearance space and the control current.The proposed research ensures the performance of the radial magnetic bearing with permanent magnet bias,and provides theory basis for design of the magnetic bearing wheel. 展开更多
关键词 magnetic bearing reaction wheel radial hybrid magnetic bearing equivalent magnetic circuit current stiffness position negative stiffness tilting current stiffness tilting angular position stiffness
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Electrochemical properties of spinel LiMn_2O_4 and LiAl_(0.1)Mn_(1.9)O_(3.9)F_(0.1) synthesized by solid-state reaction 被引量:6
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作者 Tao Li Weihua Qiu +1 位作者 Hailei Zhao Jingjing Liu 《Journal of University of Science and Technology Beijing》 CSCD 2008年第2期187-191,共5页
Two types of spinel cathode powders, LiMn2O4 and LiAl0.1Mn1.9O3.9F0.1, were synthesized by solid-state reaction, X-ray diffraction (XRD) patterns of the prepared samples were identified as the spinel structure with ... Two types of spinel cathode powders, LiMn2O4 and LiAl0.1Mn1.9O3.9F0.1, were synthesized by solid-state reaction, X-ray diffraction (XRD) patterns of the prepared samples were identified as the spinel structure with a space group of Fd 3^- m. The cubic lattice parameter was determined from least-squares fitting of the XRD data. The LiAl0.1Mn1.9O3.9F0.1 sample showed a little lower initial capacity, but better cycling performance than the LiMn2O4 sample at both room temperature and an elevated temperature. The Vanderbilt method was used to test the electrochemical conductivity of the LiMn2O4 samples. The electrochemical impedance spectroscopy (EIS) method was employed to investigate the electrochemical properties of these spinel LiMn2O4 samples. 展开更多
关键词 lithium-ion batteries positive materials LIMN2O4 solid-state reaction electrochemical properties DOPING
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SOLVABILITY OF A NONLINEAR PROBLEM ARISING IN REACTIONS OVER INHOMOGENEOUS SURFACES
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作者 Vladas SKAKAUSKAS 《Acta Mathematica Scientia》 SCIE CSCD 2019年第5期1380-1396,共17页
The existence and uniqueness theorem of classical solutions of a coupled system of nonlinear parabolic PDEs arising in modelling of chemical reactions between two polymeric reactants over inhomogeneous surfaces with n... The existence and uniqueness theorem of classical solutions of a coupled system of nonlinear parabolic PDEs arising in modelling of chemical reactions between two polymeric reactants over inhomogeneous surfaces with nonclassical boundary conditions is proved and the long-time behaviour of the solution is studied. 展开更多
关键词 coupled PARABOLIC systems positive solutions of differential EQUATIONS surface reactionS SPILLOVER
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一种拉帕替尼衍生物的合成及抗HER2阳性乳腺癌作用研究
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作者 朱星枚 郭凯丽 +8 位作者 袁盼盼 姜宇 姚琳 张东旭 刘继平 王斌 蔡盈盈 张美文 张兵兵 《中南药学》 CAS 2024年第9期2261-2265,共5页
目的合成一种拉帕替尼的衍生物,探讨其抗HER2阳性乳腺癌的作用和作用机制。方法以阿司匹林为酰化试剂,应用Steglich酯化反应,经DCC-DMAP催化合成了乙酰化拉帕替尼(化合物Ⅰ)。应用CCK8及平板克隆法考察化合物Ⅰ抗HER2阳性乳腺癌细胞增... 目的合成一种拉帕替尼的衍生物,探讨其抗HER2阳性乳腺癌的作用和作用机制。方法以阿司匹林为酰化试剂,应用Steglich酯化反应,经DCC-DMAP催化合成了乙酰化拉帕替尼(化合物Ⅰ)。应用CCK8及平板克隆法考察化合物Ⅰ抗HER2阳性乳腺癌细胞增殖的能力,采用分子对接技术预测化合物Ⅰ的作用靶点,通过Western blot法揭示化合物Ⅰ对BT474细胞AMPK/mTOR通路蛋白的影响。结果化合物Ⅰ的结构经1H NMR、13C NMR和MS确证。化合物Ⅰ对BT474细胞的IC50分别为(112.05±3.21)nmol·L^(-1)(24 h)、(35.87±0.79)nmol·L^(-1)(48 h)和(4.98±0.05)nmol·L^(-1)(72 h);化合物Ⅰ可显著抑制BT474细胞的克隆形成;分子对接结果显示化合物Ⅰ与EGFR、HER2、AMPK、mTOR和AKT1均有较好的结合;Western blot结果显示化合物Ⅰ可显著上调p-AMPK、AMPK,且激动作用较拉帕替尼更强,化合物Ⅰ亦可显著下调EGFR、HER2、p-AKT1、AKT1、p-mTOR和mTOR。结论化合物Ⅰ较拉帕替尼有更强的抗HER2阳性乳腺癌增殖活性,其主要通过激动AMPK,抑制AKT1和mTOR,调节AMPK/mTOR通路发挥作用。 展开更多
关键词 拉帕替尼衍生物 Steglich酯化反应 抗增殖 HER2阳性乳腺癌
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猪萨佩罗病毒聚合酶链式反应检测方法的建立及应用
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作者 张伟 韩寅卓 姜永厚 《浙江理工大学学报(自然科学版)》 2024年第5期718-724,共7页
猪萨佩罗病毒(Porcine sapelovirus,PSV)是引发猪腹泻的重要病毒之一。为开发一种能快速、准确检测PSV的聚合酶链式反应检测方法,针对PSV的保守区3D基因设计了一对特异性引物,优化了聚合酶链式反应退火温度,分析聚合酶链式反应检测方法... 猪萨佩罗病毒(Porcine sapelovirus,PSV)是引发猪腹泻的重要病毒之一。为开发一种能快速、准确检测PSV的聚合酶链式反应检测方法,针对PSV的保守区3D基因设计了一对特异性引物,优化了聚合酶链式反应退火温度,分析聚合酶链式反应检测方法特异性和灵敏度,并应用于猪场样品检测。结果表明:建立的聚合酶链式反应检测方法可特异性扩增出PSV目的片段,对其他非靶标猪腹泻病毒则无条带产生,检测低限为5拷贝/μL;在浙江地区采集的88个健康猪粪便样本中检测PSV阳性率为7.95%。该PSV聚合酶链式反应检测方法特异性强、灵敏度高,可应用于PSV前期诊断和防控。 展开更多
关键词 猪萨佩罗病毒 3D基因 聚合酶链式反应 特异性 灵敏度 阳性率
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布地奈德福莫特罗吸入联合气道正压通气治疗阻塞性睡眠呼吸暂停低通气综合征合并慢性阻塞性肺疾病的效果
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作者 阚海峰 马兰玉 陈龙 《中国卫生标准管理》 2024年第21期142-146,共5页
目的探讨布地奈德福莫特罗联合气道正压通气吸入剂治疗阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea-hypopnea syndrome,OSAHS)合并慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)的临床效果。方法选取2022... 目的探讨布地奈德福莫特罗联合气道正压通气吸入剂治疗阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea-hypopnea syndrome,OSAHS)合并慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)的临床效果。方法选取2022年1月—2023年12月如皋市人民医院呼吸内科收治的60例OSAHS合并COPD患者,采用随机数字抽样法分为粉雾剂组和正压组,每组30例。正压组采用气道正压通气治疗,此基础上粉雾剂组患者增加布地奈德福莫特罗吸入治疗,观察2组患者睡眠呼吸暂停改善情况,并比较2组肺功能及生活质量改善情况。结果粉雾剂组治疗后肺活量(vital capacity,VC)和第1秒用力呼气容积(forced expiratory volume in one second,FEV1)分别为(4.12±0.75)L和(3.59±0.75)L,高于正压组的(3.71±0.85)L和(2.78±0.42)L,差异均有统计学意义(P<0.05)。粉雾剂组呼吸频率(respiratory rate,RR)为(14.13±3.29)次/min,低于正压组的(16.11±2.69)次/min,差异有统计学意义(P<0.05)。粉雾剂组最低血氧饱和度水平为(98.02±2.47)%,高于正压组的(94.52±1.93)%,差异有统计学意义(P<0.05)。粉雾剂组治疗后呼吸暂停指数、低通气指数、呼吸暂停低通气指数、与呼吸事件相关微觉醒指数低于正压组,最低血氧饱和度水平高于正压组,差异有统计学意义(P<0.05)。粉雾剂组治疗后生活质量评分高于正压组,差异有统计学意义(P<0.05)。粉雾剂组患者不良反应总发生率为6.67%(2/30),与正压组的6.67%(2/30)比较,差异无统计学意义(P>0.05)。结论在气道正压通气基础上,联合布地奈德福莫特罗吸入治疗,可有效提升治疗效果,改善患者睡眠呼吸暂停病情,提升肺功能,对患者生活质量提升显著,且不良反应风险较低,临床应用价值较高。 展开更多
关键词 布地奈德福莫特罗 气道正压通气 阻塞性睡眠呼吸暂停 慢性阻塞性肺疾病 联合治疗 不良反应
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Identification of the optimal doping position of hetero-atoms in chalcogen-doped Fe-N-C catalysts for oxygen reduction reaction 被引量:1
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作者 Weihao Liu Huanhuan He +2 位作者 Qingtao Liu Xin Wan Jianglan Shui 《Particuology》 SCIE EI CAS CSCD 2024年第6期99-108,共10页
The excellent oxygen reduction reaction(ORR)activity of Fe–N–C catalysts in acidic media makes them potential for low-cost proton exchange membrane fuel cells.In recent years,it has been shown that heteroatoms(B,O,S... The excellent oxygen reduction reaction(ORR)activity of Fe–N–C catalysts in acidic media makes them potential for low-cost proton exchange membrane fuel cells.In recent years,it has been shown that heteroatoms(B,O,S,P,Cl,F,etc.)can be used as electron-withdrawing groups to modulate the planar structure and electron distribution of the Fe–Nx active sites to achieve simultaneous improvement of catalytic activity and stability.However,the optimal location of the heteroatoms remains unclear.Here,taking chalcogen heteroatoms(S and Se)as an example,we control the doping positions and investigate their effect on the ORR performance of the Fe–N–C catalysts.The first coordination shell of the iron single atom is identified as the optimal doping position.The optimized catalysts Fe–N_(3)Se_(1)/NC and Fe–N_(3)Se_(1)/NC demonstrate improved activity and stability in both half cells and fuel cells.This work provides insights into the enhancement mechanism of heteroatom doping in single-atom catalysts. 展开更多
关键词 Oxygen reduction reaction Fe-N-C catalysts Hetero-atom doping Doping position Enhancement mechanism
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维生素B1注射液皮肤过敏试验反应性和治疗安全性分析 被引量:1
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作者 钟婉君 黄小慧 楼国东 《浙江临床医学》 2024年第3期437-439,共3页
目的 分析维生素B1注射液皮肤过敏试验结果和治疗安全性。方法 收集2020年1月至2021年12月行维生素B1皮试患者的临床资料,分析患者皮试阳性率和相关因素,皮试后维生素B1肌注或使用其他维生素B1制剂的不良反应发生率。结果 维生素B1皮试... 目的 分析维生素B1注射液皮肤过敏试验结果和治疗安全性。方法 收集2020年1月至2021年12月行维生素B1皮试患者的临床资料,分析患者皮试阳性率和相关因素,皮试后维生素B1肌注或使用其他维生素B1制剂的不良反应发生率。结果 维生素B1皮试阳性率为17.07%。共549例皮试阴性患者肌注维生素B1注射液,不良反应发生率为0.95%,其中1例为严重过敏反应。59例皮试阳性患者接受静脉补充复方水溶性维生素或口服含维生素B1制剂治疗,均未发现不良反应。结论 维生素B1皮试阳性率高,可能存在假阳性和假阴性,需更深入探讨维生素B1皮试预测过敏的价值,完善相关规章制度。 展开更多
关键词 维生素B1注射液 皮肤过敏试验 阳性 过敏 不良反应
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基于临界半衰期的连续流反应热安全风险评估方法
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作者 盛敏 田均均 +2 位作者 王芳芳 李玮晔 吴展华 《含能材料》 EI CAS CSCD 北大核心 2024年第3期298-311,共14页
为了更好地评估连续流反应热安全风险,研究以通道式反应器为例,通过构建基于热量衡算和物料衡算的反应体系模型,对连续流反应体系的实际传热量和热安全风险进行了研究。针对通道式反应器进口端的绝热温升反应现象,提出了临界半衰期作为... 为了更好地评估连续流反应热安全风险,研究以通道式反应器为例,通过构建基于热量衡算和物料衡算的反应体系模型,对连续流反应体系的实际传热量和热安全风险进行了研究。针对通道式反应器进口端的绝热温升反应现象,提出了临界半衰期作为热安全判据的方法,获得了具有热安全高风险的两大反应条件,分别为:当目标反应产热总量大于800 J·g^(-1),且该反应在反应温度下半衰期小于临界半衰期;当分解反应产热总量大于800 J·g^(-1),且目标反应在反应温度下半衰期小于临界半衰期,同时分解反应在100%MTSR(工艺反应能够达到的最高温度)下半衰期也小于临界半衰期。并且通过氯苯硝化反应验证其准确性和实用性,结果显示,通道式反应器在该条件下可发生分解爆炸反应,证实了该评估方法可用于确定连续流反应热安全的高风险条件。 展开更多
关键词 通道式反应器 传热速率 绝热温升反应 反应安全风险评估方法 分解爆炸事故
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在禽类与人之间传播的禽流感反应扩散模型
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作者 田苗苗 刘俊利 《湖北民族大学学报(自然科学版)》 CAS 2024年第2期276-284,共9页
为了研究禽类和人的流动性对禽流感传播的影响,考虑禽和人的流动性,建立了一个禽流感在禽与人之间传播的反应扩散模型。首先证明了模型解的全局存在性,其次利用下一代算子的谱半径方法计算了模型的基本再生数,并分析了模型的阈值动力学... 为了研究禽类和人的流动性对禽流感传播的影响,考虑禽和人的流动性,建立了一个禽流感在禽与人之间传播的反应扩散模型。首先证明了模型解的全局存在性,其次利用下一代算子的谱半径方法计算了模型的基本再生数,并分析了模型的阈值动力学,证明了无病稳态的稳定性、疾病的持久性以及正稳态的存在性。最后通过数值模拟,验证了模型的理论结果。结果表明,对染病禽类进行隔离,从而降低禽与人的接触率可有效控制禽流感的传播。 展开更多
关键词 禽流感 反应扩散 全局渐近稳定性 基本再生数 持久性 正稳态
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益生菌联合铋剂四联对幽门螺杆菌阳性慢性胃炎患者上腹疼痛、反酸嗳气、恶心呕吐评分的影响 被引量:2
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作者 王霞 《河北医药》 CAS 2024年第15期2312-2315,共4页
目的 探讨益生菌联合铋剂四联治疗幽门螺杆菌(H.pylori)阳性慢性胃炎患者对其上腹疼痛,反酸嗳气,恶心呕吐评分的影响。方法 将2020年1月至2021年6月消化内科治疗的146例幽门螺杆菌(H.pylori)阳性慢性胃炎患者随机分为2组,对照组使用铋... 目的 探讨益生菌联合铋剂四联治疗幽门螺杆菌(H.pylori)阳性慢性胃炎患者对其上腹疼痛,反酸嗳气,恶心呕吐评分的影响。方法 将2020年1月至2021年6月消化内科治疗的146例幽门螺杆菌(H.pylori)阳性慢性胃炎患者随机分为2组,对照组使用铋剂四联疗法治疗,观察组使用益生菌联合铋剂四联疗法治疗,比较2组临床疗效、H.pylori根除率、症状评分、血清胃肠激素指标、血清炎性因子指标、不良反应。结果 观察组治疗有效率为94.52%,明显高于对照组的79.45%(P<0.05);观察组H.pylori根除率为87.67%,明显高于对照组的61.64%(P<0.05);观察组治疗后上腹疼痛、反酸嗳气、恶心呕吐等症状评分明显低于对照组(P<0.05);观察组治疗后血清胃蛋白酶原(PG)Ⅰ、PGⅠ/Ⅱ明显高于对照组,PGⅡ、G-17明显低于对照组(P<0.05);观察组治疗后白细胞介素-2(IL-2)、前列腺素E2(PGE2)、热休克蛋白(HSPs)水平明显高于对照组,IL-4、IL-10水平明显低于对照组(P<0.05);观察组头晕、失眠、恶心、腹胀、皮疹、腹泻、便秘等不良反应发生率明显低于对照组(P<0.05)。结论 益生菌联合铋剂四联治疗H.pylori阳性慢性胃炎的效果显著,能有效提高H.pylori根除率,缓解上腹疼痛、反酸嗳气、恶心呕吐等症状,调节血清胃肠激素水平,抑制胃黏膜炎症损伤,且能降低药物不良反应,具有积极的临床意义。 展开更多
关键词 慢性胃炎 幽门螺杆菌阳性 益生菌 铋剂四联疗法 疗效 症状评分 血清胃肠激素 不良反应
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基于经筋理论探讨“绕肩胛”与颈痛伴旋转功能障碍的对应关系
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作者 张思懿 龚智超 +4 位作者 刘磊 陈沁涛 郭艺 李武 李江山 《湖南中医药大学学报》 CAS 2024年第3期445-449,共5页
目的立足于经筋古籍原文,发现“绕肩胛”与手阳明、手太阳经筋相关,并从两条经筋与颈痛伴旋转功能障碍的联系入手,探讨“绕肩胛”相关经筋与颈痛伴旋转功能障碍是否存在对应关系。方法收集20例颈痛伴功能障碍的肩胛区域疼痛志愿者,对肩... 目的立足于经筋古籍原文,发现“绕肩胛”与手阳明、手太阳经筋相关,并从两条经筋与颈痛伴旋转功能障碍的联系入手,探讨“绕肩胛”相关经筋与颈痛伴旋转功能障碍是否存在对应关系。方法收集20例颈痛伴功能障碍的肩胛区域疼痛志愿者,对肩胛区8个阳性反应点进行触诊,根据疼痛部位以及颈部旋转功能障碍的类型,探索二者之间的对应规律。结果10例旋转伴后伸功能受限患者,在肩胛上区出现阳性反应点为9例,符合占比90%;10例旋转伴前屈功能受限患者,在肩胛下区出现阳性反应点为9例,符合占比90%。因而旋转伴后伸功能受限与肩胛上区、旋转伴前屈功能受限与肩胛下区存在对应关系。结论手阳明经筋与旋转伴后伸功能受限、手太阳经筋与旋转伴前屈功能受限存在对应关系。 展开更多
关键词 经筋 颈痛 绕肩胛 阳性反应点 旋转功能障碍 手阳明经筋 手太阳经筋 分布规律
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临床输血检验中不规则抗体检验的应用 被引量:1
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作者 张文杰 《实用检验医师杂志》 2024年第1期89-92,共4页
目的探讨临床输血检验中不规则抗体检验的应用价值。方法选择2022年6月—2023年6月平邑县人民医院收治的2260例输血治疗患者作为研究对象,所有患者输血前均接受不规则抗体检验,统计输血不良反应发生率,分析不规则抗体检出情况及阳性分... 目的探讨临床输血检验中不规则抗体检验的应用价值。方法选择2022年6月—2023年6月平邑县人民医院收治的2260例输血治疗患者作为研究对象,所有患者输血前均接受不规则抗体检验,统计输血不良反应发生率,分析不规则抗体检出情况及阳性分型。结果2260例输血患者中检出不规则抗体阳性40例,阳性检出率为1.77%,其中抗-M分型29例,占比最高,可达72.50%,其次是抗-E分型5例,占比为12.50%;输血不良反应发生率为1.02%(23/2260)。女性、有妊娠史女性、有输血史人群的不规则抗体阳性检出率[分别为2.55%(28/1098)、3.53%(21/1595)、3.24%(29/895)]均明显高于男性、无妊娠史女性和无输血史人群[分别为1.03%(12/1162)、1.39%(7/503)、0.81%(11/1365)],差异均有统计学意义(均P<0.05)。结论在临床输血前实施不规则抗体检验意义重大,可准确检出不规则抗体,保证输血治疗的安全性,避免严重输血反应发生。 展开更多
关键词 输血 不规则抗体检验 抗体阳性率 输血不良反应
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近20年耳穴阳性反应点研究动态与思考
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作者 李晓倩 程素仪 +1 位作者 马海燕 艾炳蔚 《中医药临床杂志》 2024年第1期1-6,共6页
耳穴是分布于耳廓上的反应点,目前被广泛应用于中医临床。耳穴疗法具有简便、无创、安全、效佳等优势,对于内、外、妇、儿等多学科疾病起到了满意的诊疗效果。耳穴阳性反应点是指人体脏腑或机体发生病变时,在耳廓相应部位发生颜色、形... 耳穴是分布于耳廓上的反应点,目前被广泛应用于中医临床。耳穴疗法具有简便、无创、安全、效佳等优势,对于内、外、妇、儿等多学科疾病起到了满意的诊疗效果。耳穴阳性反应点是指人体脏腑或机体发生病变时,在耳廓相应部位发生颜色、形态、电阻值等的异常表现。耳穴阳性反应点在不同的疾病、不同的个体或同一疾病、同一个体的不同阶段中往往具有差异性和特异性,可呈现出不同的理化特性。在传统的耳穴基础上,通过观察、触诊、电测法等手段精准探测其阳性反应点,从而更加个体化、更加精准地指导临床研究和实践,是目前耳穴领域的研究趋势之一。大量临床试验证明,耳穴阳性反应点对于治未病、诊断和治疗疾病意义重大,但目前对于耳穴阳性反应点的研究与应用缺乏规范性,如作用机制尚无统一定论,且如何做到耳穴精准探测尚未完善等。因此,该领域仍需相关学者进一步研究以指导临床实践,提高临床疗效。该文通过查阅近20年来耳穴阳性反应点相关文献,了解耳穴阳性反应点的研究进展,从耳穴的中医渊源、西医发展、现代机理探讨、耳穴探测手段、取穴规律、临床意义等方面加以归纳总结,并进行思考与讨论。 展开更多
关键词 耳穴 阳性反应点 敏感点 研究进展
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