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Multicaloric and coupled-caloric effects 认领
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作者 郝嘉政 胡凤霞 +11 位作者 尉紫冰 沈斐然 周厚博 高怡红 乔凯明 李佳 张丞 梁文会 王晶 何峻 孙继荣 沈保根 《中国物理B:英文版》 SCIE EI CAS CSCD 2020年第4期31-40,共10页
The multicaloric effect refers to the thermal response of a solid material driven by simultaneous or sequential application of more than one type of external field.For practical applications,the multicaloric effect is... The multicaloric effect refers to the thermal response of a solid material driven by simultaneous or sequential application of more than one type of external field.For practical applications,the multicaloric effect is a potentially interesting strategy to improve the efficiency of refrigeration devices.Here,the state of the art in multi-field driven multicaloric effect is reviewed.The phenomenology and fundamental thermodynamics of the multicaloric effect are well established.A number of theoretical and experimental research approaches are covered.At present,the theoretical understanding of the multicaloric effect is thorough.However,due to the limitation of the current experimental technology,the experimental approach is still in progress.All these researches indicated that the thermal response and effective reversibility of multiferroic materials can be improved through multicaloric cycles to overcome the inherent limitations of the physical mechanisms behind single-field-induced caloric effects.Finally,the viewpoint of further developments is presented. 展开更多
关键词 multicaloric effect coupled-caloric effect solid-state refrigeration magnetocaloric effect
Impact of Controlling Shareholder Equity Pledge on Corporate Value 认领
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作者 Haifeng Li Haiyi He Yuanyuan Zhang 《经济科学研究(英文)》 2020年第1期55-65,共11页
As an innovative financing behavior,equity pledge breaks the limit of traditional financing,and broadens the financing channels of companies and major shareholders.This paper comprehensively considers the impact of co... As an innovative financing behavior,equity pledge breaks the limit of traditional financing,and broadens the financing channels of companies and major shareholders.This paper comprehensively considers the impact of controlling shareholder equity pledge on corporate value from three research perspectives.The main conclusions are as follows:(1)When the equity pledge is not considered,the cash flow rights and voting rights of the company owned by the controlling shareholder are positively correlated with corporate value.That is,this presents incentive effect,but the existence of the separation of the two powers brings the second type of agency problem and reduces corporate value.(2)When considering the equity pledge,the controlling shareholder’s equity pledge may weaken the incentive effect and strengthen the encroachment effect which causing a reduction of corporate value.(3)Based on the accounting point of view,the controlling shareholder’s equity pledge is negatively correlated with the corporate performance,while the concentration of ownership dilutes this negative effect.(4)The balance of equity weakens the negative effect of the controlling shareholder’s equity pledge on corporate value,thereby reduces the negative impact of the equity pledge. 展开更多
关键词 Separation of POWERS EQUITY checks and balances EQUITY concentration INCENTIVE EFFECT ENCROACHMENT EFFECT
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Spatiotemporal Variation of Plant Diversity Under a Unique Estuarine Wetland Gradient System in the Yellow River Delta, China 认领
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作者 SUN Jingkuan CHI Yuan +2 位作者 FU Zhanyong LI Tian DONG Kaikai 《中国地理科学:英文版》 SCIE CSCD 2020年第2期217-232,共16页
Multiple natural and human factors in estuarine wetlands result in complicated land surface characteristics with distinct spatial and temporal heterogeneities,thereby contributing to the difficulty in identifying spat... Multiple natural and human factors in estuarine wetlands result in complicated land surface characteristics with distinct spatial and temporal heterogeneities,thereby contributing to the difficulty in identifying spatiotemporal variations and influencing factors of plant diversity.A unique estuarine wetland gradient system(UEWGS)consisting of soil,vegetation,heat,distance,landscape,and anthropogenic gradients was established based on the ecological features of estuarine wetland through remote sensing and field investigation methods.It resolved the complicated land surface characteristics,covered all aspects of factors influencing plant diversity,and possessed distinct spatiotemporal heterogeneities.The Yellow River Delta,the largest estuarine wetland in the northern China,was selected as the study area to demonstrate UEWGS in four seasons in 2017.A total of 123 species were recorded with considerable seasonal difference.Phragmites australis,Suaeda salsa,and Tamarix chinensis were the dominant species,and crop species also played important roles.In single effect,all aspects of gradients exerted significant influences,yet only vegetation gradient possessed significant influences in all seasons.In comprehensive effect,soil,vegetation,heat,and distance gradients showed significant gross influences.Moisture content in soil gradient and net primary productivity in vegetation gradient possessed significant net influences in all seasons and can be considered as the main driving factor and indicator,respectively,of plant diversity.The results validated the significance of UEWGS in revealing the plant diversity spatiotemporal characteristics and influencing factors,and UEWGS possessed universal applicability in the spatiotemporal analysis of plant diversity in estuarine areas. 展开更多
关键词 plant diversity SPATIOTEMPORAL variation single EFFECT comprehensive EFFECT YELLOW River Delta
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Effect of Using Mouthwash Solution on Commensal Flora of the Oral Cavity among Female Students in Qassim University 认领
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作者 Shaden Mohammed Alhathloul Amal Hussain Mohammed Ali 《生物科学与医学(英文)》 2020年第3期135-142,共8页
Oral health is the pathway to one’s general health and wellness. Mouthwash is a product used as an adjunct to oral hygiene practices as an antiseptic and antiplaque and antimicrobial agent. The awareness of using mou... Oral health is the pathway to one’s general health and wellness. Mouthwash is a product used as an adjunct to oral hygiene practices as an antiseptic and antiplaque and antimicrobial agent. The awareness of using mouthwash solution is so limited worldwide. And maybe there’s effect of mouthwash on commensal flora. The aim of this study is to measure the effect of using Mouthwash solution on commensal flora of the oral cavity. In this study, we determined three groups, the first group is considered as a basic group where Female students are not using any mouthwash, the second group used mouthwash twice daily for two weeks, group number three used mouthwash twice weekly. We take cytological sample scraping from oral cavity. All the cytological sections of all groups stained with Papanicolaou stain and examined the slides under the microscope. The study came out with the following results: The basic group that did not use any mouthwash remained unchanged, while the second group, who used mouthwash twice daily, showed a clear epithelial tissue for any bacteria and a clear background. Group number three, who used mouthwash twice a week, showed countable bacteria in epithelial tissue with a clear background. Finally, the study concluded: Cosmetic mouthwash solution has a bad effect on commensal flora if you over used it and leads to killing all your normal flora in oral cavity as much as therapeutic mouthwash will do. 展开更多
关键词 MOUTHWASH COMMENSAL Oral FLORA PAPANICOLAOU Stain AWARENESS EFFECT
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An analytical model to predict diffusion induced intermetallic compounds growth in Cu-Sn-Cu sandwich structures 认领
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作者 Yuexing Wang Yao Yao Leon Keer 《力学快报:英文版》 CAS CSCD 2020年第1期33-37,共5页
A mass diffusion model is developed to describe the growth kinetics of Cu6Sn5 intermetallic compounds(IMC)in the Cu-Sn-Cu sandwich structure.The proposed model is based on the local interfacial mass conversation law w... A mass diffusion model is developed to describe the growth kinetics of Cu6Sn5 intermetallic compounds(IMC)in the Cu-Sn-Cu sandwich structure.The proposed model is based on the local interfacial mass conversation law where interfacial Cu/Sn reactions and atomic diffusion are considered.Theoretical analysis shows that the IMC thickness growth is proportional to the square root of the product of the diffusion coefficient and time.The proposed model can explain the polarity effect of electromigration on kinetics of IMC growth where all the parameters have clear physical meaning.The theoretical predictions are compared with experimental results and show reasonable accuracy. 展开更多
关键词 INTERMETALLIC compounds Polarity EFFECT ELECTROMIGRATION DIFFUSION Size EFFECT
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Experimental Study on Analgesia and Hemostasis of Paris polyphylla,Scutellaria baicalensis and Their Compatibility 认领
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作者 Shibo ZHAO Suoyi HUANG +6 位作者 Zhenjing SI Lanlan GAN Shusheng HUANG Ye FU Jianjie LAN Xueying YU Yuekong CEN 《药用植物研究:英文版》 2020年第2期33-37,共5页
[Objectives]The analgesic and hemostatic effects of Paris polyphylla,Scutellaria baicalensis,and their compatibility were studied.[Methods](i)In the experiment on the writhing of mice induced by acetic acid,60 Kunming... [Objectives]The analgesic and hemostatic effects of Paris polyphylla,Scutellaria baicalensis,and their compatibility were studied.[Methods](i)In the experiment on the writhing of mice induced by acetic acid,60 Kunming SPF mice were randomly selected,and were randomly divided into 6 groups according to the male-to-female ratio of 1∶1,including blank control group,P.polyphylla group,S.baicalensis group,and three P.polyphylla and S.baicalensis compatibility groups(with the ratio of 1∶2,1∶1 and 1∶2).There were 10 mice in each group.In the experimental groups,the mice were given 1 g/mL Chinese medicine extract according to a dose of 20 mL/kg.In the control group,the mice were given 0.9%normal saline in equal volumes.Gavage was performed one time every 24 h and lasted for 14 d.1 h after the gavage on the 14th day,they were given 0.5%glacial acetic acid solution via intraperitoneal injection.(ii)In the hot plate experiment,60 Kunming SPF mice were selected,and the ratio of male to female,grouping,administration and gavage were the same as those of the glacial acetic acid-induced writhing experiment.Gavage was lasted for 14 d.1 h after the gavage on the 14th day,the mice were placed on a hot plate apparatus at(55±0.5)℃,and the time of licking hindfoot was measured.(iii)The hemostatic effect was explored through three experimental methods of tail hemostasis,femoral artery hemostasis and liver hemostasis.60 Kunming SPF mice were taken in each of the three experiments,and the male-female ratio and grouping were the same as above.The powder was covered on the surface of the wound sites,and the bleeding was observed.The hemostatic time was recorded,and the hemostatic time was recorded as 3 min if it exceeded 3 min.[Results](i)In the acetic acid-induced writhing experiment,compared with the blank control group,the pain of mice in the experimental groups was inhibited.Among them,P.polyphylla group,S.baicalensis group,compatibility 1∶2 group,compatibility 1∶1 group,and compatibility 2∶1 group had significant eff 展开更多
关键词 PARIS polyphylla SCUTELLARIA baicalensis Compatibility ANALGESIC EFFECT Hemostatic EFFECT
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Revisiting anisotropy in the tensile and fracture behavior of cold-rolled316L stainless steel with heterogeneous nano-lamellar structures 认领
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作者 Zesheng You Huangliu Fu +2 位作者 Shoudao Qu Weikang Bao Lei Lu 《纳米材料科学:英文版》 CAS 2020年第1期72-79,共8页
We produced a 316 L stainless steel with heterogeneous nanometer-thick lamellar structures by severe cold-rolling at room temperature,and conducted micro-scale tensile tests in different orientations to evaluate both ... We produced a 316 L stainless steel with heterogeneous nanometer-thick lamellar structures by severe cold-rolling at room temperature,and conducted micro-scale tensile tests in different orientations to evaluate both the inplane(parallel to the nano-lamellae)and out-of-plane(normal and 45inclined to the nano-lamellae)mechanical anisotropy.The parallel orientation demonstrates the greatest tensile strength while the inclined orientation exhibits the least strength.The tensile tests in normal and inclined directions also indicate significant transient elastic-plastic response due to the strain path change.Fractographic examination demonstrates that the specimen fails in the normal direction by premature micro-void nucleation and growth,which restricts its tensile strength;however,we identified zig-zag cracking associated with lamellar shear cracking in the inclined direction. 展开更多
关键词 Heterogeneous nano-lamellar structure Mechanical anisotropy Fracture behavior Specimen size effect Strain path effect
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A study of clock effects in Newton-Maxwell formalism 认领
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作者 Sankar Hajra 《大地测量与地球动力学:英文版》 2020年第1期72-77,共6页
Many measurements on the time gain/loss of the atomic clocks orbiting the spinning Earth have been done.The time gain/loss of the atomic clocks orbiting the spinning Earth is called gravitomagnetic clock effects.Clock... Many measurements on the time gain/loss of the atomic clocks orbiting the spinning Earth have been done.The time gain/loss of the atomic clocks orbiting the spinning Earth is called gravitomagnetic clock effects.Clock effects have been well studied from the consideration of the relativity theory and the effects are thought to be relativistic sequels.However,no studies has been done from the physics of Newton and the electrodynamics of Maxwell.In this paper,we have studied clock effects from Newton-Maxwell consideration and have shown that clock effects could be considered as simple consequences of Newton’s physics and Maxwell’s electrodynamics. 展开更多
关键词 CLOCK EFFECT ELECTRODYNAMICS GRAVITATION CORIOLIS EFFECT
Energy cooperation in quantum thermoelectric systems with multiple electric currents 认领
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作者 刘叶锋 陆金成 +2 位作者 王荣倩 王晨 蒋建华 《中国物理B:英文版》 SCIE EI CAS CSCD 2020年第4期199-207,共9页
The energy efficiency and output power of a quantum thermoelectric system with multiple electric currents and only one heat current are studied.The system is connected to the hot heat bath(cold bath)through one termin... The energy efficiency and output power of a quantum thermoelectric system with multiple electric currents and only one heat current are studied.The system is connected to the hot heat bath(cold bath)through one terminal(multiple terminals).In such configurations,there are multiple thermoelectric effects coexisting in the system.Using the Landauer–Buttiker formalism,we show that the cooperation between the two thermoelectric effects in the three-terminal thermoelectric systems can lead to markedly improved performance of the heat engine.Such improvement also occurs in four-terminal thermoelectric heat engines with three output electric currents.Cooperative effects in these multi-terminal thermoelectric systems can considerably enlarge the physical parameter region that realizes high energy efficiency and output power.For refrigeration,we find that the energy efficiency can also be substantially improved by exploiting the cooperative effects in multi-terminal thermoelectric systems.All these results reveal a useful approach toward high-performance thermoelectric energy conversion in multi-terminal mesoscopic systems. 展开更多
关键词 thermoelectric effect THERMODYNAMICS cooperative effect
保乳手术与改良根治术治疗早期乳腺癌的临床效果及安全性分析 认领
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作者 蒋炳涧 《当代医学》 2020年第2期82-84,共3页
目的研究保乳手术与改良根治手术对于早期乳腺癌患者的作用与效果。方法选取本院在2015年10月至2019年1月采用改良根治手术的53例早期乳腺癌患者,将其作为A组;另选同期采用保乳手术的53例早期乳腺癌患者,将其作为B组,观察比较两组临床... 目的研究保乳手术与改良根治手术对于早期乳腺癌患者的作用与效果。方法选取本院在2015年10月至2019年1月采用改良根治手术的53例早期乳腺癌患者,将其作为A组;另选同期采用保乳手术的53例早期乳腺癌患者,将其作为B组,观察比较两组临床效果及安全性。结果B组患者在治疗后其各手术指标、并发症发生率、美容总优良率均优于A组(P<0.05)。结论对于早期乳腺癌患者,运用保乳手术后,治疗后的效果与质量优于改良根治手术,还能够辅助维持乳房所具有的美观,值得临床推广。 展开更多
关键词 保乳手术 治疗 改良根治术 效果 康复效果 早期乳腺癌
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两种宫颈施源器清洗方法效果比较 认领
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作者 李雪梅 《护理研究》 北大核心 2020年第3期517-518,共2页
[目的]探讨宫颈施源器不同清洗方法的实施效果。[方法]2016年6月—2016年12月我科共接收宫颈施源器1245套,随机抽取300套设为对照组。2017年1月—2017年6月接受宫颈施源器1362套,随机抽取300套设为观察组。对照组采用手工清洗、水枪冲... [目的]探讨宫颈施源器不同清洗方法的实施效果。[方法]2016年6月—2016年12月我科共接收宫颈施源器1245套,随机抽取300套设为对照组。2017年1月—2017年6月接受宫颈施源器1362套,随机抽取300套设为观察组。对照组采用手工清洗、水枪冲洗、酸化水消毒、干燥柜干燥,观察组采用手工清洗、超声清洗、酸化水消毒、低温干燥。采用目测法、5倍光源放大镜、潜血试验检测两组的清洗效果。[结果]清洗后对照组与观察组目测合格率分别是92%、98%,5倍光源放大镜合格率分别是91%、97%,清洗后对照组与观察组潜血试验阴性率分别是89%、97%,清洗后的损耗率分别是7%、1%。两组目测合格率、5倍光源放大镜合格率、潜血试验阴性率、清洗后的损耗率比较差异均有统计学意义(P<0.05)。[结论]我院消毒供应中心制定的宫颈施源器清洗的标准化程序可以明显提高清洗效果。 展开更多
关键词 宫颈癌 宫颈施源器 放疗 清洗方法 效果 目测法 5倍光源放大镜 潜血试验
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Synthesis and Electronic Structure of Triazasubporphyrin with Peripherally Low Symmetric Push-pull Substitutions 认领
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作者 樊宇轩 袁太艳 +3 位作者 吕庆洋 李敏智 朱卫华 梁旭 《结构化学》 SCIE CAS CSCD 2020年第1期36-40,2共6页
Peripherally low symmetric substitution with electron-donating(EDG)and electron-withdrawing(EWG)substituents caused the rational modulation of geometric structure and even the electronic structure of triazasubporphyri... Peripherally low symmetric substitution with electron-donating(EDG)and electron-withdrawing(EWG)substituents caused the rational modulation of geometric structure and even the electronic structure of triazasubporphyrin,the smallest 14πconjugated aza-porphyrinoids.Both structural characterization and spectroscopic investigation were discussed to provide an in-depth understanding of the relationship between peripheral push-pull substituents and SubPz core. 展开更多
关键词 triazasubporphyrin PUSH-PULL effect ELECTRONIC structure seterochemistry
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中医艾灸技术在1例眼科病房带入性糖尿病足病人护理中的应用效果 认领
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作者 汤福静 张娇 薛阳阳 《全科护理》 2020年第12期1535-1536,共2页
回顾总结某院病房收治的1例带入性糖尿病足的眼科病人护理经验,对病人进行个性化护理、减轻病人消极情绪,调动配合治疗的积极性,对足部创面采取消毒、药物外涂及中医艾灸技术等护理措施,促进创面的愈合。中医艾灸技术在糖尿病足病人的... 回顾总结某院病房收治的1例带入性糖尿病足的眼科病人护理经验,对病人进行个性化护理、减轻病人消极情绪,调动配合治疗的积极性,对足部创面采取消毒、药物外涂及中医艾灸技术等护理措施,促进创面的愈合。中医艾灸技术在糖尿病足病人的护理中有修复创面作用,并且对病人进行有效的健康教育及正确的足部护理措施,可以提高糖尿病足的治愈率,从而提高病人的生活质量。 展开更多
关键词 中医艾灸 糖尿病 效果
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饮食连续护理对2型糖尿病合并肥胖症患者护理质量及睡眠的影响效果分析 认领
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作者 刘玉敏 《世界睡眠医学杂志》 2020年第4期662-664,共3页
目的:探究饮食连续护理对2型糖尿病合并肥胖症患者护理质量及睡眠的影响效果分析。方法:选取2017年12月至2018年12月谷城县人民医院收治的2型糖尿病合并肥胖症患者1200例作为研究对象,按照入院先后就诊顺序随机分为对照组和观察组,每组... 目的:探究饮食连续护理对2型糖尿病合并肥胖症患者护理质量及睡眠的影响效果分析。方法:选取2017年12月至2018年12月谷城县人民医院收治的2型糖尿病合并肥胖症患者1200例作为研究对象,按照入院先后就诊顺序随机分为对照组和观察组,每组600例。其中对照组患者仅予以基础护理,而观察组则在此基础上增加予以饮食连续护理,通过不同方式后比较护理前后所有患者的睡眠质量、护理后各项指标以及护理效果。结果:进行护理前2组患者的睡眠质量评分较为相似,差异无统计学意义(P>0.05),通过不同方式的有效护理之后,2组患者的睡眠质量均得到有效提升,观察组患者的睡眠质量明显优于对照组患者,差异有统计学意义(P<0.05);观察组患者在空腹血糖、餐后2 h血糖、糖化血红蛋白、总胆固醇以及BMI等指标也明显优于对照组患者,差异有统计学意义(P<0.05);并且观察组患者护理后的总有效率高达(94.33%)远远优于对照组患者(83.33%),差异有统计学意义(P<0.05)。结论:在临床治疗2型糖尿病合并肥胖症患者过程中应用饮食连续护理是能够有效保障患者护理以及睡眠质量的,将患者各项血糖指标控制进行有效控制,延缓疾病发展增加恢复,值得在临床之中大力推广并应用。 展开更多
关键词 饮食连续护理 2型糖尿病 肥胖症患者 护理质量 睡眠 影响效果
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Barrier Effect of a Membrane on Malodorous Gases 认领
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作者 Tingting ZHANG Yonggang XUE +1 位作者 Qunbiao HE Xia LIU 《气象与环境研究:英文版》 CAS 2020年第1期58-60,65共4页
After the experimental research on the barrier effect of PTFE membrane on malodorous gases,it was found that PTFE membrane had good gas permeability,and the barrier effect on malodorous gases NH3 and H2S was poor. Aft... After the experimental research on the barrier effect of PTFE membrane on malodorous gases,it was found that PTFE membrane had good gas permeability,and the barrier effect on malodorous gases NH3 and H2S was poor. After a layer of water film was formed on PTFE membrane,it had an obvious barrier effect on malodorous gases NH3 and H2S. 展开更多
关键词 PTFE MEMBRANE Malodorous GASES BARRIER EFFECT
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鼻内镜下口鼻联合径路行腺样体切除治疗腺样体肥大的疗效观察 认领
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作者 梁建超 《广东医科大学学报》 2020年第2期206-209,共4页
目的观察鼻内镜下口鼻联合径路行腺样体切除治疗腺样体肥大的疗效。方法 86例腺样体肥大患儿,按照不同的治疗方式分为研究组和对照组,每组43例。研究组采取鼻内镜下口鼻联合径路行腺样体切除术,对照组采取常规腺样体刮除术。比较两组的... 目的观察鼻内镜下口鼻联合径路行腺样体切除治疗腺样体肥大的疗效。方法 86例腺样体肥大患儿,按照不同的治疗方式分为研究组和对照组,每组43例。研究组采取鼻内镜下口鼻联合径路行腺样体切除术,对照组采取常规腺样体刮除术。比较两组的疗效、手术时间、术中出血量及干预前后鼻咽部最小横截面积、并发症发生率(感染、鼻腔狭窄、鼻腔粘连等)及复发率、干预前后的日常生活能力(QOL)评分。结果研究组的疗效优于对照组,手术时间、术中出血量少于对照组(P<0.05或0.01);干预后,研究组的鼻咽部最小横截面积大于对照组(P<0.05),食欲、精神、睡眠、疲乏及日常生活评分均高于对照组(P<0.01)。研究组复发率为4.65%,明显低于对照组23.26%(P<0.05)。两组并发症发生率分别为4.65%、18.60%,差异尚未达统计学意义(P>0.05)。结论鼻内镜下口鼻联合径路行腺样体切除运用于腺样体肥大中效果显著,减少治疗时长,降低并发症发生率和复发率,提升生活质量,促进早日康复。 展开更多
关键词 疗效观察 腺样体肥大 鼻内镜 腺样体切除 腺样体刮除术
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催化裂解工艺技术对现在化工的作用 认领
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作者 罗奕科 《广东化工》 CAS 2020年第7期121-123,共3页
催化裂解工艺技术是近代研发和利用的化工型炼油工艺技术,它的运用淘汰了一些落后的传统技术,生产了大量的化工原料,极大程度上缓解了随着我国乃至世界经济发展所带来对化工原料日益增长需求而不能满足的矛盾。它的产生可以实现炼油与... 催化裂解工艺技术是近代研发和利用的化工型炼油工艺技术,它的运用淘汰了一些落后的传统技术,生产了大量的化工原料,极大程度上缓解了随着我国乃至世界经济发展所带来对化工原料日益增长需求而不能满足的矛盾。它的产生可以实现炼油与化工的有机结合,促进石油化工产业进一步发展,并向更广的领域扩伸发挥作用,解决能耗高,环境污染重,操作弹性差,设备投资高,目的产品收率低等一系列问题。催化裂解工艺技术对现在化工的作用意义非常重大,我们要了解,重视,推广催化裂解工艺技术。 展开更多
关键词 催化裂解工艺技术 化工原料 作用 研究和运用
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分析外科手术联合药物治疗胆结石患者的效果 认领
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作者 王彬 《中国实用医药》 2020年第1期25-26,共2页
目的研究外科手术联合药物治疗胆结石患者的效果。方法 100例胆结石患者,根据入院顺序分为观察组和对照组,每组50例。观察组患者实施外科手术联合药物治疗,对照组患者实施外科手术治疗。比较两组患者手术指标、总胆红素(TBIL)、谷丙转氨... 目的研究外科手术联合药物治疗胆结石患者的效果。方法 100例胆结石患者,根据入院顺序分为观察组和对照组,每组50例。观察组患者实施外科手术联合药物治疗,对照组患者实施外科手术治疗。比较两组患者手术指标、总胆红素(TBIL)、谷丙转氨酶(ALT)水平、治疗效果。结果观察组患者手术时间(48.23±1.23)min、住院时间(6.32±1.09)d、肛门排气时间(20.33±1.23)h均短于对照组的(72.33±1.53)min、(12.34±1.84)d、(43.20±1.83)h,术中出血量(60.45±1.84)ml少于对照组的(152.55±2.09)ml,差异具有统计学意义(P<0.05)。术后30 d,两组患者TBIL、ALT水平均低于本组术后1 d,且观察组低于对照组,差异具有统计学意义(P<0.05)。观察组患者治疗总有效率为96.00%,高于对照组的72.00%,差异具有统计学意义(P<0.05)。结论外科手术联合药物治疗胆结石患者的效果十分显著,且能够使其各项指标得到改善,值得推广。 展开更多
关键词 外科手术 药物治疗 胆结石 效果
Tailoring edge and interface states in topological metastructures exhibiting the acoustic valley Hall effect 认领
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作者 Jiao Wang Yang Huang WeiQiu Chen 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2020年第2期82-92,共11页
In this study, we investigate the acoustic topological insulator or topological metastructure, where an acoustic wave can exist only in an edge or interface state instead of propagating in bulk. Breaking the structura... In this study, we investigate the acoustic topological insulator or topological metastructure, where an acoustic wave can exist only in an edge or interface state instead of propagating in bulk. Breaking the structural symmetry enables the opening of the Dirac cone in the band structure and the generation of a new band gap, wherein a topological edge or interface state emerges.Further, we systematically analyze two types of topological states that stem from the acoustic valley Hall effect mechanism;one type is confined to the boundary, whereas the other type can be observed at the interface between two topologically different structures. Results denote that the selection of different boundaries along with appropriately designed interfaces provides the acoustic waves in the band gap range with abilities of one-way propagation, dual-channel propagation, immunity from backscattering at sharp corners, and/or transition between propagation at interfaces and boundaries. Furthermore, we show that the acoustic wave propagation paths can be tailored in diverse and arbitrary ways by combing the two aforementioned types of topological states. 展开更多
关键词 ACOUSTIC crystals VALLEY Hall effect EDGE STATES interface STATES Dirac cone
Synthesis and Characterization of Dinuclear Rare Earth Complexes Bearing N-heterocyclic Olefin Moieties 认领
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作者 张敏 孙江华 +1 位作者 孙维林 倪旭峰 《结构化学》 SCIE CAS CSCD 2020年第1期79-85,3共8页
The oxygen-bridged dinuclear rare earth complexes(Ln=Nd(1),Y(2))bearing N-heterocyclic olefin moieties were synthesized by treating the imidazolidinium salt[SIMes-H]Br with potassium amide and rare earth bis(trimethyl... The oxygen-bridged dinuclear rare earth complexes(Ln=Nd(1),Y(2))bearing N-heterocyclic olefin moieties were synthesized by treating the imidazolidinium salt[SIMes-H]Br with potassium amide and rare earth bis(trimethylsilyl)amides.Complex 1 was characterized by X-ray diffraction analysis and complex 2 was characterized by 1H NMR spectroscopy.Both complexes were characterized by elemental analysis.Crystal data of complex 1:C74H138O2N8Si8Nd2,Mr=1685.12,orthorhombic,space group Pbca,a=25.1105(7),b=11.9188(2),c=29.6151(7)?,V=8863.4(4)?^3,Z=4,Dc=1.263 g·cm^-3,μ=1.311 mm^-1,F(000)=3544,the final R=0.0418 and wR=0.0770 for all data.The ring-opening of tetrahydrofuran molecule was proven,the possible mechanism for the formation of N-heterocyclic olefin(NHO)-rare earth complexes was speculated and the electronic and steric properties of SIMes and rare earth amides were discussed.This work provides a better understanding of N-heterocyclic carbene rare earth chemistry. 展开更多
关键词 rare earth complex N-heterocyclic OLEFIN N-heterocyclic CARBENE SIMes STERIC effect
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