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Design and Analysis of Power and Transmission System of Downhole Pure Electric Command Vehicle
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作者 Md Jahangir Alam Md Shahriar Sujan +1 位作者 Md. Al Imran Tapu Joy Howlader 《Journal of Transportation Technologies》 2024年第1期31-52,共22页
Electric vehicles use electric motors, which turn electrical energy into mechanical energy. As electric motors are conventionally used in all the industry, it is an established development site. It’s a mature technol... Electric vehicles use electric motors, which turn electrical energy into mechanical energy. As electric motors are conventionally used in all the industry, it is an established development site. It’s a mature technology with ideal power and torque curves for vehicular operation. Conventional vehicles use oil and gas as fuel or energy storage. Although they also have an excellent economic impact, the continuous use of oil and gas threatened the world’s reservation of total oil and gas. Also, they emit carbon dioxide and some toxic ingredients through the vehicle’s tailpipe, which causes the greenhouse effect and seriously impacts the environment. So, as an alternative, electric car refers to a green technology of decarbonization with zero emission of greenhouse gases through the tailpipe. So, they can remove the problem of greenhouse gas emissions and solve the world’s remaining non-renewable energy storage problem. Pure electric vehicles (PEV) can be applied in all spheres, but their special implementation can only be seen in downhole operations. They are used for low noise and less pollution in the downhole process. In this study, the basic structure of the pure electric command vehicle is studied, the main components of the command vehicle power system, namely the selection of the drive motor and the power battery, are analyzed, and the main parameters of the drive motor and the power battery are designed and calculated. The checking calculation results show that the power and transmission system developed in this paper meets the design requirements, and the design scheme is feasible and reasonable. 展开更多
关键词 pure Electric Vehicles TRANSMISSION GEARS Electronic Differential Control Algorithms
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Stable operation of highly loaded pure Si-Fe anode under ambient pressure via carboxy silane-directed robust solid electrolyte interphase
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作者 Guntae Lim Dong Guk Kang +6 位作者 Hyeon Gyu Lee Yen Hai Thi Tran Kihun An Junghyun Choi Kwang Chul Roh Do Youb Kim Seung-Wan Song 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期568-576,共9页
Incorporation of higher content Si anode material beyond 5 wt% to Li-ion batteries(LIBs)is challenging,owing to large volume change,swelling,and solid electrolyte interphase(SEI)instability issues.Herein,a strategy of... Incorporation of higher content Si anode material beyond 5 wt% to Li-ion batteries(LIBs)is challenging,owing to large volume change,swelling,and solid electrolyte interphase(SEI)instability issues.Herein,a strategy of diacetoxydimethylsilane(DAMS)additive-directed SEI stabilization is proposed for a stable operation of Si-0.33FeSi_(2)(named as Si-Fe)anode without graphite,which provides siloxane inorganics and organics enrichment that compensate insufficient passivation of fluoroethylene carbonate(FEC)additive and reduce a dependence on FEC.Unprecedented stable cycling performance of highly loaded(3.5 mA h cm^(-2))pure Si-Fe anode is achieved with 2 wt%DAMS combined with 9 wt%FEC additives under ambient pressure,yielding high capacity 1270 mA h g^(-1)at 0.5 C and significantly improved capacity retention of 81% after 100 cycles,whereas short circuit and rapid capacity fade occur with FEC only additive.DAMS-directed robust SEI layer dramatically suppresses swelling and particles crossover through separator,and therefore prevents short circuit,demonstrating a possible operation of pure Si or Sidominant anodes in the next-generation high-energy-density and safe LIBs. 展开更多
关键词 High-energy Li-ion battery pure Si-Fe anode without graphite Silane additive SEI layer Suppressed swelling
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Strongly Coupled Ag/Sn-SnO_(2)Nanosheets Toward CO_(2)Electroreduction to Pure HCOOH Solutions at Ampere‑Level Current
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作者 Min Zhang Aihui Cao +5 位作者 Yucui Xiang Chaogang Ban Guang Han Junjie Ding Li‑Yong Gan Xiaoyuan Zhou 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期212-226,共15页
Electrocatalytic reduction of CO_(2) converts intermittent renewable electricity into value-added liquid products with an enticing prospect,but its practical application is hampered due to the lack of high-performance... Electrocatalytic reduction of CO_(2) converts intermittent renewable electricity into value-added liquid products with an enticing prospect,but its practical application is hampered due to the lack of high-performance electrocatalysts.Herein,we elaborately design and develop strongly coupled nanosheets composed of Ag nanoparticles and Sn-SnO_(2) grains,designated as Ag/Sn-SnO_(2) nanosheets(NSs),which possess optimized electronic structure,high electrical conductivity,and more accessible sites.As a result,such a catalyst exhibits unprecedented catalytic performance toward CO_(2)-to-formate conversion with near-unity faradaic efficiency(≥90%),ultrahigh partial current density(2,000 mA cm^(−2)),and superior long-term stability(200 mA cm^(−2),200 h),surpassing the reported catalysts of CO_(2) electroreduction to formate.Additionally,in situ attenuated total reflection-infrared spectra combined with theoretical calculations revealed that electron-enriched Sn sites on Ag/Sn-SnO_(2)NSs not only promote the formation of*OCHO and alleviate the energy barriers of*OCHO to*HCOOH,but also impede the desorption of H*.Notably,the Ag/Sn-SnO_(2)NSs as the cathode in a membrane electrode assembly with porous solid electrolyte layer reactor can continuously produce~0.12 M pure HCOOH solution at 100 mA cm^(−2)over 200 h.This work may inspire further development of advanced electrocatalysts and innovative device systems for promoting practical application of producing liquid fuels from CO_(2). 展开更多
关键词 Electrochemical CO_(2)reduction Coupled Ag/Sn-SnO_(2)nanosheets Electronic structure Porous solid electrolyte pure
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围长至少为6平面图的injective-染色
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作者 卜月华 杨强 《浙江师范大学学报(自然科学版)》 CAS 2023年第2期121-131,共11页
为了进一步探究平面图的injective-染色,通过分析临界图的结构性质并利用权转移方法,证明了围长至少为6,Δ(G)≥9且6-圈与6-圈不交的平面图G,有χ_(i)(G)≤Δ(G)+1.所得结果推广了平面图injective-染色的已知结果.
关键词 injective-染色 平面图 围长 最大度
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Effect of Soursop Puree and Gum Arabic on the Sensory Properties of Non-Dairy Coconut Milk-Based Ice Cream
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作者 Sarah N. Mulwa Symon M. Mahungu Benard K. Muinde 《Food and Nutrition Sciences》 2023年第7期670-686,共17页
Coconut (Cocos nucifera) milk-based ice cream is one of the innovative non-dairy milk products gaining popularity among consumers. The objective was to develop coconut milk-based ice cream incorporated with soursop (A... Coconut (Cocos nucifera) milk-based ice cream is one of the innovative non-dairy milk products gaining popularity among consumers. The objective was to develop coconut milk-based ice cream incorporated with soursop (Annona muricata) fruit puree and gum Arabic from Acacia senegal var. kerensis, conduct a sensory evaluation using descriptive tests by trained panelists (n = 9) then evaluate for consumer acceptability by semi trained panelists (n = 30). A seven-point hedonic scale for colour, taste, flavour, texture and overall acceptability was used. The data obtained was subjected to analysis of variance (ANOVA) and the means were separated to determine their significance differences. Principal Component Analysis (PCA) was done for factor reduction to make it easy for the multi-dimensional descriptive data to be interpreted. PCA results indicated that unit increase in soursop and gum Arabic in the ice cream led to 83.1% increase in starchy taste, 78.3% increase in consistency and 73.6% decrease in coconut aroma. For consumer acceptability test, the obtained results showed that, soursop puree addition at successive levels led to a statistically significant effect (p < 0.05) on colour, flavour, texture, taste and overall acceptability while of gum Arabic incorporation was not significant (p > 0.05) for all attributes. The effect due to interaction between gum Arabic and soursop puree at the different levels however was significant for colour, flavour and texture but not significant for taste and overall acceptability. Our results therefore point to a potential application of soursop fruit and gum Arabic as alternative ingredients in the manufacture of a non-dairy ice cream with desirable sensory properties that would expand the variety of options consumers can choose from. 展开更多
关键词 Consumer Acceptability Ice Cream Non-Dairy Sensory Properties Soursop puree
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Underlying mechanisms of variation in yield asymmetry and strain hardening behavior of extruded pure Mg with Gd addition
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作者 Gyo Myeong Lee Sung Hyuk Park 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第6期2165-2181,共17页
Effects of Gd addition on the strain hardening behavior and yield asymmetry of pure Mg are investigated by subjecting extruded pure Mg,Mg–5Gd,and Mg–15Gd(all in wt%)to tension and compression tests along the extrusi... Effects of Gd addition on the strain hardening behavior and yield asymmetry of pure Mg are investigated by subjecting extruded pure Mg,Mg–5Gd,and Mg–15Gd(all in wt%)to tension and compression tests along the extrusion direction(ED).As the amount of Gd added to pure Mg increases,the basal texture tilts toward the ED and the distribution of c-axes of grains becomes randomized.Under tension,the strain hardening rates of all the materials decrease until fracture.However,under compression,the strain hardening rate increases in the early stage of deformation in pure Mg and Mg–5Gd,whereas it continuously decreases in Mg–15Gd.Pure Mg exhibits considerably high tension-compression yield asymmetry,with a compressive yield strength(CYS)to tensile yield strength(TYS)ratio of 0.4.In contrast,Mg–5Gd exhibits excellent yield symmetry with CYS/TYS of 0.9 and Mg–15Gd exhibits reversed yield asymmetry with CYS/TYS of 1.2.Underlying mechanisms of these drastically different Gd-addition-induced deformation behaviors of the materials are discussed in terms of the crystallographic distribution of grains and the relative activation stresses of basal slip,prismatic slip,pyramidal slip,and{10–12}twinning under tension and compression. 展开更多
关键词 pure Mg Gd addition TEXTURE Yield asymmetry Activation stress
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Tension-Compression Asymmetry in Ultrafine-grained Commercially Pure Ti Processed by ECAP
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作者 刘晓燕 LI Shuaikang +1 位作者 YANG Xirong LUO Lei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期689-694,共6页
A homogenous microstructure of ultrafine-grained (UFG) commercially pure (CP) Ti characterized by equiaxed grains/subgrains with an average grain size of about 150 nm and strong prismatic fiber texture were obtained a... A homogenous microstructure of ultrafine-grained (UFG) commercially pure (CP) Ti characterized by equiaxed grains/subgrains with an average grain size of about 150 nm and strong prismatic fiber texture were obtained after 4 passes of equal channel angular pressing (ECAP).Tension–compression asymmetry in yield and work hardening behavior of UFG CP Ti were investigated by uniaxial tension and compression tests.The experimental results reveal that UFG CP Ti exhibits a relatively obvious tensioncompression asymmetry in yielding and work hardening behavior.The basal and prismaticslip are suppressed either for tension or compression,which is the easiest to activate.The tension twin system{1012}<1011> easily activated in compression deformation due to the prismatic fiber texture based on the Schmidt factor,consequently resulting in a lower yield strength under compression than tension.ECAP can improve the tension-compression asymmetry of CP Ti due to grain refinement.The interaction among the dislocations,grain boundaries and deformation twins are the main work hardening mechanisms for compression deformation,while the interaction between the dislocations and grain boundaries for tension deformation.Deformation twins lead to the higher work hardening under compression than tension. 展开更多
关键词 ultrafine-grained commercially pure Ti equal channel angular pressing tensioncompression asymmetry texture TWINNING
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Complexity of Injective Homomorphisms to Small Tournaments, and of Injective Oriented Colourings
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作者 Russell J. Campbell Nancy E. Clarke Gary MacGillivray 《Open Journal of Discrete Mathematics》 2023年第1期1-15,共15页
Several possible definitions of local injectivity for a homomorphism of an oriented graph G to an oriented graph H are considered. In each case, we determine the complexity of deciding whether there exists such a homo... Several possible definitions of local injectivity for a homomorphism of an oriented graph G to an oriented graph H are considered. In each case, we determine the complexity of deciding whether there exists such a homomorphism when G is given and H is a fixed tournament on three or fewer vertices. Each possible definition leads to a locally-injective oriented colouring problem. A dichotomy theorem is proved in each case. 展开更多
关键词 injective Graph Homomorphism Oriented Colouring COMPLEXITY
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An Investigation of Purely Azimuthal Passive Localization and Position Adjustment in Attempted UAV Formation Flights
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作者 Qi Zhang Keren Sun Qiaozhen Zhang 《Journal of Applied Mathematics and Physics》 2023年第10期3075-3098,共24页
When a cluster of unmanned aerial vehicles (UAVs) is flying in formation, it is crucial to maintain the formation and not to be interfered by external electromagnetic wave signals. In order to maintain the formation, ... When a cluster of unmanned aerial vehicles (UAVs) is flying in formation, it is crucial to maintain the formation and not to be interfered by external electromagnetic wave signals. In order to maintain the formation, this paper proposes to use pure azimuth passive positioning to adjust the position of UAVs, i.e., certain UAVs in the formation transmit signals, the rest of the UAVs receive the signals passively, and extract the orientation information from them to adjust the position of the UAVs [1] [2] [3]. In this paper, the position adjustment problem of UAVs in “circular” formation flight under three models is investigated. To address the problem of “how to obtain the position of the receiving UAV when there are two UAVs with known numbers and evenly distributed on the circumference in addition to the UAV transmitting at the known center of the circle, and the rest of the UAVs with slight deviations in their positions are receiving the signals”, two purely mathematical geometric methods, namely, triangular localization method and polar co-ordinate method, are proposed respectively. We have determined the position of the receiving UAV;we have used the exhaustive method and the construction and disproof method to solve the problem of “how many UAVs are needed to transmit signals in order to realize the effective positioning of the UAVs when it is known that a certain UAV with a slight deviation in its position receives the signals emitted by two UAVs at the same time”, and the results show that: in addition to the known signals emitted by two UAVs, it is also necessary to transmit the signals emitted by two UAVs. The results show that in addition to the known two UAVs transmitting signals, two additional UAVs are required to transmit signals for precise po-sitioning. When the position of UAVs has deviation at the initial moment, the ideal approximation method and the target delimitation method are pro-posed, and the target of nine UAVs uniformly distributed on a circle of a spe-cific radius is achieved through several adjustments, after which the ad-vantages and disadvantages of each model are analyzed, and suggestions for improvement are put forward. The purely azimuthal passive localization method and the constructed model approach proposed in this paper can be extended to other fields, such as spacecraft formations in space and battle-ship formations at sea, as well as other formation flight position adjustment problems. 展开更多
关键词 pure Azimuth Passive Positioning Unmanned Aerial Vehicle (UAV) Position Adjustment Electromagnetic Silence
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Effect of Strain Ratio on Fatigue Model of Ultra-fine Grained Pure Titanium
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作者 QIANG Meng YANG Xirong +1 位作者 LIU Xiaoyan LUO Lei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第5期1169-1178,共10页
The ultra-fine grained(UFG)pure titanium was prepared by equal channel angular pressing(ECAP)and rotary swaging(RS).The strain controlled low cycle fatigue(LCF)test was carried out at room temperature.The fatigue life... The ultra-fine grained(UFG)pure titanium was prepared by equal channel angular pressing(ECAP)and rotary swaging(RS).The strain controlled low cycle fatigue(LCF)test was carried out at room temperature.The fatigue life prediction model and mean stress relaxation model under asymmetrical stress load were discussed.The results show that the strain ratio has a significant effect on the low cycle fatigue performance of the UFG pure titanium,and the traditional Manson-coffin model can not accurately predict the fatigue life under asymmetric stress load.Therefore,the SWT mean stress correction model and three-parameter power curve model are proposed,and the test results are verified.The final research shows that the threeparameter power surface model has better representation.By studying the mean stress relaxation phenomenon under the condition of R≠-1,it is revealed that the stress ratio and the strain amplitude are the factors that significantly afiect the mean stress relaxation rate,and the mean stress relaxation model with the two variables is calculated to describe the mean stress relaxation phenomenon of the UFG pure titanium under different strain ratios.The fracture morphology of the samples was observed by SEM,and it was concluded that the final fracture zone of the fatigue fracture of the UFG pure titanium was a mixture of ductile fracture and quasi cleavage fracture.The toughness of the material increases with the increase of strain ratio at the same strain amplitude. 展开更多
关键词 ultra-fine grained pure titanium low cycle fatigue life model mean stress relaxation mode strain ratio fracture morphology
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Philosophical Matrix as a System of Categories of Pure Mind
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作者 Yuriy Rotenfeld 《Journal of Philosophy Study》 2023年第6期269-274,共6页
The article is a study devoted to the development of the concept of the philosophical matrix as a system of categories of pure reason.The author proposes a new approach to understanding the philosophical system of cat... The article is a study devoted to the development of the concept of the philosophical matrix as a system of categories of pure reason.The author proposes a new approach to understanding the philosophical system of categories by putting forward unambiguous comparative concepts that serve as the basis for natural sciences.While the foundations of specific sciences are the concepts of“practical reason”,the author finds the categories of“pure reason”to be the foundations of philosophy,understood as“knowledge of the universal”.The article shows that relying on the senses and the concepts of“practical reason”allows for the verification of knowledge,while their generalization,removed from knowledge obtained empirically,gives categories of“pure reason”,which are accepted as the building material of the matrix.In this way,the author proposes a new system of philosophical categories that describes the fundamental aspects of human reasoning and its interaction with the world.At the same time,the categories of the philosophical matrix are not related to such ambiguous classificatory concepts as space,time,being,existence,consciousness,and others.The article draws attention to the fact that the matrix can be used not only to analyze philosophical theories but also to develop new concrete scientific approaches,for example,for the intellectual development of children.In addition,the article suggests the possibility of applying the philosophical matrix in other areas of the humanities,including psychology,linguistics,and sociology.As a result of the conducted research,the human intellect is divided into three ascending stages,designated by me in the following words-reason,mind,and wisdom,with the subsequent use of these concepts in philosophy and other fields of knowledge. 展开更多
关键词 REASON MIND wisdom CONTRADICTORY correlated opposite philosophical matrix practical mind pure mind
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基于宏基因组测序和纯培养技术解析胀袋生抽酱油的微生物类群 被引量:1
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作者 王玉荣 席啦 +3 位作者 易宗伟 付彩霞 葛东颖 郭壮 《食品与发酵工业》 CAS CSCD 北大核心 2024年第4期165-170,177,共7页
该研究采用宏基因组测序技术对胀袋生抽酱油微生物类群进行了解析,对其微生物菌株进行了分离鉴定,并对分离株是否可导致酱油胀气进行了验证。宏基因组结果表明,胀袋生抽酱油样品中平均相对含量大于1.0%的微生物主要由嗜盐四联球菌(Tetra... 该研究采用宏基因组测序技术对胀袋生抽酱油微生物类群进行了解析,对其微生物菌株进行了分离鉴定,并对分离株是否可导致酱油胀气进行了验证。宏基因组结果表明,胀袋生抽酱油样品中平均相对含量大于1.0%的微生物主要由嗜盐四联球菌(Tetragenococcus halophilus)、酸鱼联合乳杆菌(Ligilactobacillus acidipiscis)、植物乳植物杆菌(Lactiplantibacillus plantarum)、耐酸乳杆菌(Lactobacillus acetotolerans)、棒状腐败乳杆菌(Loigolactobacillus coryniformis)、短促生乳杆菌(Levilactobacillus brevis)和屎肠球菌(Enterococcus faecium)构成,平均相对含量分别为28.01%、25.50%、9.45%、2.49%、1.83%、1.53%和1.33%;采用纯培养技术,分离出的49株细菌被鉴定为6个属下的11个种,其中枯草芽孢杆菌(Bacillus subtilis)、破布子联合乳杆菌(Ligilactobacillus pobuzihii)、蛋白原酶腐败乳杆菌(Loigolactobacillus rennini)和L.acidipiscis分离株占总分离株数的39.22%、19.61%、11.76%和9.80%,分离出的2株酵母菌均被鉴定为扣囊复膜酵母(Saccharomycopsis fibuligera);产气验证实验发现,所有分离株均不能单独引起生抽酱油的胀袋现象。由此可见,胀袋生抽酱油具有较高的微生物多样性,在后续研究引入培养组学策略以获得更多的分离株,亦或考虑多菌株的协同作用,对酱油涨袋这一产业问题的解决可能具有积极的意义。 展开更多
关键词 生抽酱油 胀气 宏基因组测序 纯培养 微生物
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基于精密切削和抛光的铸态软金属的金相表征
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作者 孙明艳 张永皞 +1 位作者 张晓峰 黄姝珂 《热加工工艺》 北大核心 2024年第7期147-150,154,共5页
基于超精密、精密切削和抛光技术,介绍了两种表征铸态软金属材料金相组织的新方法。该方法摒弃了常规金相组织表征在试样制备过程中的磨制步骤。采用超精密切削,或者精密切削与抛光相结合的方法,解决了铸态软金属材料金相试样制备困难... 基于超精密、精密切削和抛光技术,介绍了两种表征铸态软金属材料金相组织的新方法。该方法摒弃了常规金相组织表征在试样制备过程中的磨制步骤。采用超精密切削,或者精密切削与抛光相结合的方法,解决了铸态软金属材料金相试样制备困难、重复性和稳定性差的难题,提高了制样效率和金相组织形貌显示的真实性。 展开更多
关键词 精密切削 软金属 纯锡 纯铅 金相组织
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基于BIS和微旁流EtCO_(2)监护下甲苯磺酸瑞马唑仑在日间宫腔镜手术麻醉中的有效性和安全性 被引量:1
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作者 张俊杰 杨晓春 +4 位作者 刘卓懿 吴若秋 李平 郭曲练 王锷 《实用医学杂志》 CAS 北大核心 2024年第8期1047-1051,共5页
目的研究甲苯磺酸瑞马唑仑用于日间宫腔镜手术麻醉中的有效性和安全性。方法采用随机对照设计,纳入行日间宫腔镜手术患者300例,采用随机数字随机分为两组。年龄18~60岁,BMI18.5~27 kg/m~2,ASAⅠ-Ⅱ级。R组应用甲苯磺酸瑞马唑仑,P组应用... 目的研究甲苯磺酸瑞马唑仑用于日间宫腔镜手术麻醉中的有效性和安全性。方法采用随机对照设计,纳入行日间宫腔镜手术患者300例,采用随机数字随机分为两组。年龄18~60岁,BMI18.5~27 kg/m~2,ASAⅠ-Ⅱ级。R组应用甲苯磺酸瑞马唑仑,P组应用丙泊酚作为对照。所有患者在手术开始前5 min予以舒芬太尼0.1μg/kg缓慢静脉注射。R组甲苯磺酸瑞马唑仑首剂予以0.2 mg/kg缓慢静脉注射,根据镇静深度单次予以0.05 mg/kg追加。P组丙泊酚首剂予以1.5~2 mg/kg缓慢静脉注射,根据镇静深度单次予以0.5 mg/kg追加。所有患者入室后持续监测并记录心电图、SpO_(2)、NIBP、HR、BIS、微旁流EtCO_(2)。记录所有患者的麻醉效果相关指标(包括麻醉药物起效时间、手术时间、苏醒时间及离室时间),安全性指标(低血压、低氧饱和度、恶心呕吐等不良事件),医师和患者的满意度。结果甲苯磺酸瑞马唑仑用于日间宫腔镜手术中镇静深度满足临床要求,低血压和注射痛发生率低(P<0.01),呼吸抑制更轻(P<0.05),手术时间、离室时间、恶心呕吐及满意度等差异均无统计学意义(P>0.05)。结论甲苯磺酸瑞马唑仑用于日间宫腔镜检镇静深度合适,低血压、注射痛发生率低,呼吸抑制更轻微,甲苯磺酸瑞马唑仑复合舒芬太尼可安全有效地应用于日间宫腔镜手术的麻醉。 展开更多
关键词 日间手术 甲苯磺酸瑞马唑仑 丙泊酚 宫腔镜 注射痛 低血压
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超声对乳腺单纯黏液癌与纤维腺瘤鉴别诊断的价值
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作者 王红莉 胡越 +5 位作者 谭翠 顾然 梅静思 余玥幸 陈丽莉 龚畅 《中山大学学报(医学科学版)》 CAS CSCD 北大核心 2024年第4期631-636,共6页
【目的】探讨乳腺单纯黏液癌(PMC)和纤维腺瘤(FA)的超声表现差异,为临床鉴别诊断提供参考。【方法】回顾性搜集2012年1月至2021年1月间在中山大学孙逸仙纪念医院就诊的连续乳腺PMC初诊患者50例及2018年6月至2019年1月间的连续乳腺FA初... 【目的】探讨乳腺单纯黏液癌(PMC)和纤维腺瘤(FA)的超声表现差异,为临床鉴别诊断提供参考。【方法】回顾性搜集2012年1月至2021年1月间在中山大学孙逸仙纪念医院就诊的连续乳腺PMC初诊患者50例及2018年6月至2019年1月间的连续乳腺FA初诊患者100例超声资料。依据2013年版乳腺影像报告与数据系统(BI-RADS)评估两组病变的超声图像特征,并比较两组患者年龄、病变的长径及超声图像特征的差异。【结果】PMC患者中位年龄为47岁,而FA为33岁,PMC患者年龄较FA偏大,两者差异具有统计学意义(P<0.001)。PMC患者病变中位长径2.4 cm大于FA的1.8 cm,差异有统计学意义(P=0.001)。PMC中,70%(35/50)表现为不规则形,82%(41/50)与皮肤平行,92%(46/50)边缘不清晰,72%(36/50)内部呈低回声,68%(34/50)后方回声增强;FA中,69%(69/100)表现为卵圆形或圆形,98%(98/100)与皮肤平行,54%(54/100)边缘清晰,98%(98/100)内部呈低回声,75%(75/100)后方回声未见变化,PMC与FA相应超声表现的差异有统计学意义(P<0.001,P=0.001,P<0.001,P<0.001,P<0.001),而病变内是否存在钙化、病变的血流表现在两者间差异无统计学意义。【结论】与FA相比,PMC患者年龄及病变长径偏大,并且在超声上,大部分乳腺PMC的形态及边缘仍表现为浸润性癌的生长特点,同时,PMC的后方回声增强,是其独特的表现。 展开更多
关键词 乳腺 黏液癌 单纯黏液癌 纤维腺瘤 超声
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关于n-纯同调维数的注记
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作者 吕家凤 金欣怡 《浙江师范大学学报(自然科学版)》 2024年第1期14-18,共5页
为了研究环与模的n-纯同调维数,通过同调的方法,分别给出了n-纯投射模与n-纯内射模的一些新刻画.作为应用,证明了环R的n-纯投射整体维数不超过1的充分必要条件是R的n-纯内射整体维数不超过1,得到了一个环R的n-纯投射整体维数与R的n-纯... 为了研究环与模的n-纯同调维数,通过同调的方法,分别给出了n-纯投射模与n-纯内射模的一些新刻画.作为应用,证明了环R的n-纯投射整体维数不超过1的充分必要条件是R的n-纯内射整体维数不超过1,得到了一个环R的n-纯投射整体维数与R的n-纯内射整体维数的对应关系. 展开更多
关键词 n-纯正合列 n-纯投射模 n-纯内射模 同调维数
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导向注药套管经鼻悬吊留置伴或不伴锚定治疗肺部霉菌病的操作流程 被引量:2
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作者 冯靖 刘丹 +4 位作者 万南生 王杰 句仁华 谢巍 田羽 《天津医药》 CAS 2024年第1期83-86,共4页
全身使用有效抗霉菌药物是治疗肺部霉菌病的基础治疗方法,同时,经过内镜注药是气管、支气管和肺部霉菌病最重要的治疗方式之一。相比内镜注药,导向注药套管经鼻悬吊留置伴或不伴锚定治疗肺部霉菌病具有较多优势,包括可接驳注射泵持续缓... 全身使用有效抗霉菌药物是治疗肺部霉菌病的基础治疗方法,同时,经过内镜注药是气管、支气管和肺部霉菌病最重要的治疗方式之一。相比内镜注药,导向注药套管经鼻悬吊留置伴或不伴锚定治疗肺部霉菌病具有较多优势,包括可接驳注射泵持续缓慢地注入药物,可避免反复进行呼吸内镜等。该文介绍了导向注药套管经鼻悬吊留置伴或不伴锚定治疗肺部霉菌病的操作流程。 展开更多
关键词 支气管镜 肺疾病 真菌性 导向注药套管经鼻悬吊
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Optimization of Process Parameters of Continuous Microwave Drying Raspberry Puree Based on RSM and ANN-GA
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作者 Zheng Xian-zhe Gao Feng +2 位作者 Fu Ke-sen Lu Tian-lin Zhu Chong-hao 《Journal of Northeast Agricultural University(English Edition)》 CAS 2023年第1期69-84,共16页
To improve drying uniformity and anthocyanin content of the raspberry puree dried in a continuous microwave dryer,the effects of process parameters(microwave intensity,air velocity,and drying time)on evaluation indexe... To improve drying uniformity and anthocyanin content of the raspberry puree dried in a continuous microwave dryer,the effects of process parameters(microwave intensity,air velocity,and drying time)on evaluation indexes(average temperature,average moisture content,average retention rate of the total anthocyanin content,temperature contrast value,and moisture dispersion value)were investigated via the response surface method(RSM)and the artificial neural network(ANN)with genetic algorithm(GA).The results showed that the microwave intensity and drying time dominated the changes of evaluation indexes.Overall,the ANN model was superior to the RSM model with better estimation ability,and higher drying uniformity and anthocyanin retention rate were achieved for the ANN-GA model compared with RSM.The optimal parameters were microwave intensity of 5.53 W•g^(-1),air velocity of 1.22 m·s^(-1),and drying time of 5.85 min.This study might provide guidance for process optimization of microwave drying berry fruits. 展开更多
关键词 raspberry puree continuous microwave drying response surface method(RSM) artificial neural network(ANN) genetic algorithm(GA)CLC number:TG376 Document code:A Article ID:1006-8104(2023)-01-0069-16
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热轧变形对纯钴显微组织和力学性能的影响
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作者 徐仰涛 魏江龙 南宏强 《中国有色金属学报》 EI CAS CSCD 北大核心 2024年第6期2019-2029,共11页
为研究不同热轧变形量对纯钴的显微组织和力学性能的影响,对高纯钴(99.95%)进行500℃下的热轧处理,将试样水冷后进行XRD、EBSD表征。结果表明:初始态试样中HCP相、FCC相两相共存,且以HCP相为主;随轧制进行,最大晶粒尺寸从28.08μm细化到... 为研究不同热轧变形量对纯钴的显微组织和力学性能的影响,对高纯钴(99.95%)进行500℃下的热轧处理,将试样水冷后进行XRD、EBSD表征。结果表明:初始态试样中HCP相、FCC相两相共存,且以HCP相为主;随轧制进行,最大晶粒尺寸从28.08μm细化到12.35μm,∑3退火孪晶和相变孪晶的含量降低,残余应变增加,两相含量发生改变,FCC相含量上升,HCP相含量降低;不同相中大小角度晶界呈现相同的变化趋势,小角度晶界(LAGB)含量上升,大角度晶界(HAGB)含量降低;压下量27%的试样性能最好,其屈服强度、抗拉强度、硬度和伸长率(657.18 MPa、964.05 MPa、298.2HV_(0.5)和42.87%)相较于初始态(408.34 MPa、862.53 MPa、214.4HV_(0.5)和38.07%)均有提升;塑性随强度的增加不降反升,主要是由FCC相含量上升、大尺寸片层状HCP相晶粒发生细化和均匀化所致。 展开更多
关键词 纯钴 热轧 显微组织 力学性能
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基于纯培养和超高深宏基因组测序技术分析茅台镇两企业高温大曲微生物多样性差异
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作者 王玉荣 侯强川 +3 位作者 田龙新 刘菊珍 周加平 郭壮 《食品科学》 EI CAS CSCD 北大核心 2024年第4期108-115,共8页
以茅台镇不同酒厂高温大曲为研究对象,采用纯培养技术和宏基因组测序对高温大曲中微生物多样性进行解析。结果发现,分离的212株芽孢杆菌主要为77株索诺拉沙漠芽孢杆菌(Bacillus sonorensis)、39株地衣芽孢杆菌(B. licheniformis)和19株... 以茅台镇不同酒厂高温大曲为研究对象,采用纯培养技术和宏基因组测序对高温大曲中微生物多样性进行解析。结果发现,分离的212株芽孢杆菌主要为77株索诺拉沙漠芽孢杆菌(Bacillus sonorensis)、39株地衣芽孢杆菌(B. licheniformis)和19株解淀粉芽孢杆菌(B. amyloliquefaciens)等。通过宏基因组Binning技术共获得55个高质量基因组,其中有18个疑似新菌株,分别为Bacillus sp.、Lactobacillus sp.和Weissella sp.等。菌群结构分析表明,高温大曲中的主要菌属分别为Desmospora sp. 8437、B. sonorensis和B. amyloliquefaciens等,其中A酒厂在B. sonorensis和B. amyloliquefaciens等的相对丰度显著较低(P<0.05)。A酒厂高温大曲中微生物的多样性和丰富度均显著低于B酒厂(P<0.05),且两者的菌群结构存在明显的差异。在功能方面,A酒厂高温大曲中丰度较高的差异代谢通路主要与氨基酸的生物合成相关,而B酒厂高温大曲中丰度较高的差异代谢通路主要与L-鼠李糖的降解相关。由此可见,本研究对后续发酵工艺的改良和优良菌株的筛选具有积极意义。 展开更多
关键词 高温大曲 纯培养技术 宏基因组 芽孢杆菌 生物信息学
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