Design and Analysis of Power and Transmission System of Downhole Pure Electric Command Vehicle

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.

Stable operation of highly loaded pure Si-Fe anode under ambient pressure via carboxy silane-directed robust solid electrolyte interphase

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.

Strongly Coupled Ag/Sn-SnO_(2)Nanosheets Toward CO_(2)Electroreduction to Pure HCOOH Solutions at Ampere‑Level Current

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).

Effect of Soursop Puree and Gum Arabic on the Sensory Properties of Non-Dairy Coconut Milk-Based Ice Cream

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.

Underlying mechanisms of variation in yield asymmetry and strain hardening behavior of extruded pure Mg with Gd addition

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.

Tension-Compression Asymmetry in Ultrafine-grained Commercially Pure Ti Processed by ECAP

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.

An Investigation of Purely Azimuthal Passive Localization and Position Adjustment in Attempted UAV Formation Flights

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.

Effect of Strain Ratio on Fatigue Model of Ultra-fine Grained Pure Titanium

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.

Philosophical Matrix as a System of Categories of Pure Mind

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.

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

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。

基于精密切削和抛光的铸态软金属的金相表征

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。

超声对乳腺单纯黏液癌与纤维腺瘤鉴别诊断的价值

【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。

Optimization of Process Parameters of Continuous Microwave Drying Raspberry Puree Based on RSM and ANN-GA

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.

热轧变形对纯钴显微组织和力学性能的影响

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。

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

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。

纯电动和燃油公交车的火灾发展特性数值模拟研究

为了研究纯电动和燃油公交车火灾发展特性的异同,采用FDS数值模拟方法,考虑动力电池发生热失控喷射释放可燃气体并燃烧形成喷射火,对比电池包和燃油两类典型点火源下,公交车整车燃烧的热烟释放与火灾发展特性。结果表明:对于10.5 m长的纯电动和燃油公交车火灾,火灾增长速率均位于超快速火和快速火之间,在前500 s燃油公交车的热释放速率(Heat Release Rate,HRR)大于电动公交车,然而电动公交车HRR在500 s后大于燃油车;纯电动和燃油公交车峰值热释放速率(Peak Heat Release Rate,PHRR)分别为25.4 MW和24.2 MW,总热释放量(Total Heat Release,THR)分别为20.2 GJ和17.5 GJ,电动公交车相比燃油车具有更高的PHRR和THR,但PHRR达峰时间滞后144 s;在点火源距离后门较近和火灾前期100 s门窗均处于关闭状态最不利情况下,相比燃油公交车,电动车上部内饰的引燃时间提前、下部有所延迟,后天窗附近窗户破窗时间提前;在公交车火灾发展中,电动车窗户等开口部位处溢流火的高度大于燃油车,1 min内是人员逃生关键时间,且车厢内中后部温度均高于前部。

关于n-纯同调维数的注记

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.

双层圆钢管混凝土长柱压扭滞回性能试验

为研究双层圆钢管混凝土长柱在压、扭荷载作用下的力学性能,利用研制的Stewart六自由度加载平台,进行了两个普通圆钢管混凝土长柱和两个双层圆钢管混凝土长柱试件在纯扭、压扭作用下的低周往复试验。对比分析了各试件的承载力、扭转变形、耗能、滞回性能,进行了有限元参数分析。研究表明:普通圆钢管混凝土长柱和双层圆钢管混凝土长柱均具有较好的抗扭能力;与普通圆钢管混凝土长柱相比,双层圆钢管混凝土长柱的初始刚度和承载力略有提升,滞回曲线更饱满,耗能能力和延性大幅提升;参数分析表明含钢率一定时,内层钢管径厚比越大,对抗扭越有利;一定范围内的轴向荷载,可提高钢管混凝土柱的抗扭能力。

VTI介质修正声学近似qP波波动方程与模拟

各向异性介质中纵横波通常耦合在一起传播,纵横波解耦是地震波传播理论研究的重要内容。经典的声学近似通过设置垂向qSV波速度V_(S0)为0来解耦qP波场,但是存在退化qSV波等问题。本研究将垂向qSV波速度V_(S0)考虑成波数k_(x)、k_(z)和各向异性参数ε、δ的函数,对声学近似进行修正,推导了VTI介质修正声学近似qP波频散关系和波动方程。VTI介质修正声学近似qP波波动方程包含椭圆项和非椭圆项两部分,因此采用混合有限差分/伪谱算法进行求解,即采用有限差分法求解椭圆项、伪谱法求解非椭圆项。频散关系分析和数值示例表明,基于修正声学近似的qP波波动方程不包含退化qSV波,是纯qP波方程,与弹性波方程模拟结果吻合较好,且具有较高精度;该方程在ε≥δ和ε<δ的VTI介质中均是稳定的,并且精度高于声学近似模拟结果。

远程测听技术的研究与应用进展

远程医疗是指利用信息和通信技术提供医疗保健服务。随着互联网技术的发展和普及,远程医疗得到了广泛认可和应用。远程测听技术是利用信息和通信技术提供测听服务,具有便捷性、高效性、低成本、自动化等优势,可为资源不足的地区提供测听服务,降低测听成本,提高筛查效率,为大规模大范围的听力服务提供可能。但远程测听仍存在许多局限性,可能影响测听结果的准确性和普及性。本文回顾远程测听技术的发展历程、应用现状,探讨其优势与局限性,为远程测听的进一步研究与应用提供参考。