mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
High capacity sodium-rich layered oxide cathode for sodium-ion batteries

Sodium-ion batteries have attracted significant recent attention currently considering the limited available lithium resource. However, the energy density of sodium-ion batteries is still insufficient compared to lithium-ion batteries, mainly because of the unavailability of high-energy cathode materials. In this work, a novel sodium-rich layered oxide material (Na_2MnO_3) is reported with a dynamical stability similar to that of the Li_2MnO_3 structure and a high capacity of 269.69 mA·h·g~(-1), based on first-principles calculations. Sodium ion de-intercalation and anionic reaction processes are systematically investigated, in association with sodium ions migration phenomenon and structure stability during cycling of NaxMnO3 (1 ≤ x ≤ 2). In addition, the charge compensation during the initial charging process is mainly contributed by oxygen, where the small differences of the energy barriers of the paths 2c→4h, 4h→2c, 4h→4h, 2c→2b, and 4h→2b indicate the reversible sodium ion occupancy in transitional metal and sodium layers. Moreover, the slow decrease of the elastic constants is a clear indication of the high cycle stability. These results provide a framework to exploit the potential of sodium-rich layered oxide, which may facilitate the development of high-performance electrode materials for sodium-ion batteries.
Mn-based permanent magnets

Mn-based intermetallic compounds have attracted much attention due to their fascinating structural and physical properties, especially their interesting hard magnetic properties. In this paper, we have summarized the magnetic and structural properties of Mn-based intermetallic compounds (MnX, where X = Al, Bi, and Ga). Various methods for synthesizing single phases of MnAl, MnBi, and MnxGa were developed in our lab. A very high saturation magnetization of 125 emu/g, coercivity of 5 kOe, and maximum energy product (BH)_(max) of 3.1 MG·Oe were achieved at room temperature for the pure t-Mn–Al magnetic phase without carbon doping and the extrusion process. Low temperature phase (LTP) MnBi with a purity above 95 wt.% can be synthesized. An abnormal temperature coefficient of the coercivity was observed for the LTP MnBi magnet. Its coercivity increased with temperature from 100 K to 540 K, reached a maximum of 2.5 T at about 540 K, and then decreased slowly to 1.8 T at 610 K. The positive temperature coefficient of the coercivity is related to the evolution of the structure and magnetocrystalline anisotropy field of the LTP MnBi phase with temperature. The LTP MnBi bonded magnets show maximum energy products (BH)_(max) of 8.9 MG·Oe (70 kJ/m~3) and 5.0 MG·Oe (40 kJ/m~3) at room temperature and 400 K, respectively. Ferrimagnetic MnxGa phases with L10 structures (x < 2.0) and D022 structures (x > 2.0) were obtained. All of the above structures can be described by a D022 supercell model in which 2a-Ga and 2b-Mn are simultaneously substituted. The tetragonal D022 phases of the MnxGa show high coercivities ranging from 7.2 kOe for low Mn content x = 1.8 to 18.2 kOe for high Mn content x = 3 at room temperature. The Mn_(1.2)Ga sample exhibits a room temperature magnetization value of 80 emu/g. The hard magnetic properties of coercivity iHc = 3.5 kOe, remanence M_r = 43.6 emu/g, and (BH)_(max) = 2.5 MG·Oe were obtained at room temperature. Based on the above studies, we believe that Mn-based magnetic materials could be promising candidates for rare earth free permanent magnets exhibiting a high Curie temperature, high magnetocrystalline anisotropy, and very high coercivity.
Catalytic oxidative desulfurization of fuels in acidic deep eutectic solvents with [(C6H13)3P(C14H29)]_3PMo_(12)O_(40) as a catalyst

Deep eutectic solvents(DESs) are a new class of green solvents analogous to ionic liquids due to their biodegradable capacity and low cost. However, the direct extractive desulfurization of diesel oil by DESs cannot meet the government's standard. In this work, amphiphilic polyoxometalates were synthesized and characterized by FT-IR and mass spectrometry. The oxidative desulfurization results showed that benzothiophene(BT) could be completely removed by employing a [(C_6H_(13))_3P(C_(14)H_(29))]_3PMo_(12)O_(40), DES(ChCl/2Ac) and H_2O_2 system. It was also found that the organic cation of catalysts played a positive role in oxidative desulfurization. The reaction conditions, such as reaction temperature and time, the amount of catalyst and DES and H_2O_2/S(O/S) molar ratio, were optimized. Different sulfides were tested to determine the desulfurization selectivity of the optimal reaction system, and it was found that 97.2% of dibenzothiophene(DBT) could be removed followed by 80.7% of 4-MDBT and 76.0% of 4,6-DMDBT. After reaction, the IR spectra showed that the catalyst [(C_6H_(13))3P(C_(14)H_(29))]_3PMo_(12)O_(40) was stable during the reaction process and the oxidative product was dibenzothiophene sulfone(DBTO2). Furthermore, the catalyst can be regenerated and recycled for four runs with little loss of activity.
Polyoxometalate-based silica-supported ionic liquids for heterogeneous oxidative desulfurization in fuels

With the aim of deep desulfurization, silica-supported polyoxometalate-based ionic liquids were successfully prepared by a one-pot hydrothermal process and employed in heterogeneous oxidative desulfurization of various sulfur compounds. The compositions and structures of the hybrid samples were characterized by various methods such as FT-IR, XPS, Raman, UV–Vis, wide-angle XRD and N2 adsorption–desorption. The experimental results indicated that the hybrid materials presented a high dispersion of tungsten species and excellent catalytic activity for the removal of 4,6-dimethyldibenzothiophene without any organic solvent as extractant, and the sulfur removal could reach 100.0% under mild conditions. The catalytic performance on various substrates was also investigated in detail. After cycling seven cycles, the sulfur removal of the heterogeneous system still reached 93.0%. The GC-MS analysis results demonstrated that the sulfur compound was first adsorbed by the catalyst and subsequently oxidized to its corresponding sulfone.
Experimental investigation of propagation mechanisms and fracture morphology for coalbed methane reservoirs

Fracture propagation mechanisms in coalbed methane(CBM) reservoirs are very complex due to the development of the internal cleat system. In this paper, the characteristics of initiation and propagation of hydraulic fractures in coal specimens at different angles between the face cleat and the maximum horizontal principal stress were investigated with hydraulic fracturing tests. The results indicate that the interactions between the hydraulic fractures and the cleat system have a major effect on fracture networks. ‘‘Step-like'' fractures were formed in most experiments due to the existence of discontinuous butt cleats. The hydraulic fractures were more likely to divert or propagate along the butt cleat with an increase in the angles and a decrease in the horizontal principal stress difference. An increase in the injection rate and a decrease in the fracturing fluid viscosity were more conducive to fracture networks. In addition, the influence on fracture propagation of the residual coal fines in the wellbore was also studied. The existence of coal fines was an obstacle in fracturing, and no effective connection can be formed between fractures. The experimental investigation revealed the fracture propagation mechanisms and can provide guidance for hydraulic fracturing design of CBM reservoirs.
Investigations into the coiled tubing partial underbalanced drilling (CT-PUBD) technique for drilling hard formations

To improve the rate of penetration(ROP) in drilling deep and hard formations, this paper proposes a new drilling method called coiled tubing partial underbalanced drilling(CT-PUBD). As a preliminary investigation into the new drilling method, this paper presents predictions of hole cleaning efficiency, drilling speed, cuttings migration and pressure loss in the drilling process with CT-PUBD. Based on numerical simulation and full-scale experimental studies, we conclude that using CT-PUBD, an underbalanced drilling condition can be achieved near the bit while maintaining wellbore safety at the same time. This condition can be achieved using a cuttings discharge device, a rotary packer and a backflow controller. According to the numerical simulations performed in this study, CT-PUBD can achieve high efficiency of hole cleaning. Along the cuttings migration process, the fluid velocities can reach the maximum values in the backflow holes. A full-scale laboratory experimental system was used to test the hydraulic characteristics and obtain the drilling performance of the new technology. The result shows that CT-PUBD significantly improves the ROP compared to the conventional drilling method.
A geochemical investigation of the free and carbonate-bound organic matter in the clay-sized fraction of argillaceous source rocks and its significance for biogenic interpretation

The molecular composition and biomarker distribution of various occurrences of organic matter in argillaceous source rocks developed in fresh and saline lacustrine environments were revealed by successive treatments of solvent extraction followed by acid hydrolysis using gas chromatography–mass spectrometry. The free fraction obtained by solvent extraction provided abundant geochemical information concerning the sedimentary environment, thermal maturity and biogenic origin, and obvious differences existed between fresh and saline lacustrine source rock samples. Our research results indicate that the carbonate-mineral-bound(CM-bound) fraction released by successive acid hydrolysis could also serve as a significant biogenic indicator, as the bicyclic sesquiterpenoids, indicative of Botryococcus braunii origin, were specifically detected in quite high abundance in the acid-soluble fraction. In addition, the light end hydrocarbons were much better preserved in the acid-soluble fraction, and elemental sulfur was only detected in the CM-bound fraction, suggesting a relatively confined environment for the CM-bound fraction, which thus could preserve additional geochemical information compared to that of the free fraction. The CM-bound fraction also exhibited discernable differences between fresh and saline lacustrine samples. Therefore, it can be concluded that comprehensive analysis of free and CM-bound fractions in the argillaceous source rocks can provide a more authentic and objective interpretation of geologic conditions.
尘肺合并皮疽诺卡菌肺部感染1例

皮疽诺卡菌长期存在于土壤中,是诺卡菌中较为少见的一种,腐生性兼性需氧菌,多引起亚急性或者慢性化脓性炎症,尤其是细胞免疫低下患者。该菌引起呼吸系统感染极其罕见,多为吸入性感染,而主要表现为咳嗽、咯痰、发热、乏力、消瘦,症状极度不具备特异性,同时影像学可表现为小片或者大片影,单发或多发脓肿,也有空洞及胸膜增厚、胸腔积液,与肺结核及深部真菌感染相似,区别困难,因此导致临床诊断及治疗困难。本文通过1例二期尘肺患者感染皮疽诺卡菌诊治及文献复习,希望能为临床诊治提供一定参考及帮助。
疝内容物为阑尾的腹股沟复发股疝1例报告

Amyand疝是一种特殊类型的腹股沟疝,疝内容物为阑尾。2017年2月,我们收治1例开放性腹股沟疝术后1个月发生Amyand疝,报道如下。
改善发电机阻尼的励磁系统调差系数优化设计

在实际电力系统运行中,为了保证无功负荷的合理分配,通常将励磁调差系数限制在一个较合理的范围内,而对于调差参数的整定没有明确的规定。针对该问题,提出了一种基于改善发电机动态阻尼的励磁系统调差系数优化方法。建立含调差系数的单机无穷大线性化模型,依据调差单元引入前后系统无阻尼机械振荡频率不变性,选择期望的阻尼比重新配置系统的闭环极点,由新的极点确定调差系数。通过具体算例整定调差参数,并在Matlab中进行仿真验证。仿真表明,采用优化后的励磁调差系数能够有效改善发电机动态阻尼,提高系统对低频振荡的抑制能力。
基于PWM控制的脉冲阻塞式交-交变频调速系统研究

针对采用移相控制策略的传统交-交变频电路的特点,在分析传统交流调压电路的控制策略和脉冲阻塞原理的基础上,提出了基于PWM控制的脉冲阻塞式交-交变频原理。通过对主电路拓扑结构的设计,可以实现单相输出电压基频以上的变频;依据面积等效原理对PWM高频斩波控制理论进行详细的分析,推导出了调制度的相关表达式,实现了单相输出的变频调幅。最后,设计了基于PWM控制的脉冲阻塞式三相交-交变频调速系统,并进行了仿真实验验证。理论分析与仿真结果一致,验证了该变频调速策略的正确性及可行性。
Application of computer-assisted surgery techniques in the management of zygomatic complex fractures

Patients suffering from zygomatic complex fractures always present facial deformity and dysfunctions, and thereafter develop psychological and physiological problems. It is really hard to get an ideal prognosis for the zygomatic complex fractures because of the complicated anatomical structures. Computerassisted surgery techniques, as the new emerging auxiliary methods, can optimize the surgical protocol, predict operation outcomes, and improve the accuracy and quality of the operation. Meanwhile the postoperative complications can be reduced effectively. This review aims to provide a comprehensive overview of the application of computer-assisted surgery techniques in the management of zygomatic complex fractures.
微柱凝胶法输血相容性检测弱凝集现象的影响因素分析

目的探讨微柱凝胶法在输血相容性检测中出现弱凝集的影响因素及其处理方法.方法对微柱凝胶法在ABO血型鉴定、抗体筛选及交叉配血试验中出现弱凝集的患者血标本,采用增加红细胞或血清量、2次离心血清标本、37℃洗涤红细胞及吸收放散试验进行处理后,再采用盐水法和间接抗人球蛋白法进行对照检测.结果在156例微柱凝胶法输血相容性检测出现1 +~w ~ 2 +~w弱凝集患者血标本中,ABO血型抗原性弱38例(24.4%) 、ABO抗体效价低19例(12.2%) 、ABO亚型血16例(10.3%) 、高效价冷凝集素24例(15.4%) 、纤维蛋白增高32例(20.5%) 、自身免疫性抗体27例(17.3%).156例弱凝集血标本在输血相容性检测中引起ABO血型正反定型不符129例(82.7%),抗体筛选阳性51例(32.7%).交叉配血不合99例(63.5%),其中正反定型不符合并交叉配血不合48例,交叉配血不合合并抗体筛选阳性51例.结论血型抗原性弱、抗体效价低、高效价冷凝集素、纤维蛋白增高及自身免疫性抗体的干扰,是微柱凝胶法出现弱凝集的主要影响因素.采用增加红细胞及血清量,2次离心血清标本、37℃洗涤红细胞及吸收放散试验等方法处理后,再进行检测可排除上述影响因素对检测结果的干扰.
抗I抗体引起ABO血型正反定型不符及原因分析

目的探讨患者血清中抗I抗体的血清学特点及其对输血相容性检测的影响.方法在输血相容性检测中,出现正反定型不符和交叉配血不合的患者血标本,将其红细胞用37℃生理盐水反复洗涤后,进行复查血型和直接抗人球蛋白试验;对其血清进行冷凝集素吸收试验和不规则抗体筛选,对抗体筛选阳性的患者血标本进行抗体特异性鉴定、抗体性质及抗体效价测定.结果6例患者ABO血型鉴定结果为: A型2例、B型3例、O型1例.患者血清标本在输血相容性检测中与反定型红细胞、自身红细胞、成人O型红细胞,在4℃、22℃发生1 + ~ 2 +意外凝集,与脐血O型红细胞不发生凝集,与抗体筛选细胞在37℃不凝集,说明该抗体为抗I抗体.患者直接抗人球蛋白试验抗IgG阴性、抗C3d阳性.将患者血清用2-巯基乙醇处理后,再与成人O型细胞、脐血O型细胞在4℃、22℃进行抗体检测,结果均不凝集,说明该抗体性质为IgM型.抗体效价4℃为1∶128 ~ 1∶512、22℃为1∶32 ~ 1∶64、37℃为0.结论对输血相容性检测中出现意外凝集的患者血标本,采用37℃生理盐水洗涤红细胞、抗人球蛋白试验、冷凝集素吸收试验、不规则抗体筛选及特异性鉴定;并在37℃条件下进行血型鉴定和交叉配血试验,可保证检测结果的准确性和输血安全.
On the Dual $p$-Measures of Asymmetry for Star Bodies

Recently,the connection between $p$-measures of asymmetry and the ${L_p}$-mixed volumes for convex bodies was found soon after the $p$-measure of asymmetry was proposed,and the Orlicz-measures of asymmetry was proposed inspired by such a kind of connection.In this paper,by a similar way the dual $p$-measures of asymmetry for star bodies (naturally for convex bodies) is introduced first.Then the connection between dual $p$-measures of asymmetry and ${L_p}$-dual mixed volumes is established.Finally,the best lower and upper bounds of dual $p$-measures and the corresponding extremal bodies are discussed.
单细胞测序发现内毛细胞活动诱导I型螺旋神经节分为三型

采用单细胞RNA测序的方法,Shrestha及其同事发现(图1):①内耳I型螺旋神经节神经元可分为三种亚型;②各个亚型之间以及频率响应轴不同区域的分子表达存在显著差异;③各个亚型的分化从出生后开始,依赖正常内毛细胞活动的诱导。
Influence of Joint EMSFN and M-EMS on Fluid Flow in the Mold During Continuous Casting

Homogenization of physical properties and the chemical composition through the control of liquid metal flow is essential during the continuous casting production of billets.This work was aimed at obtaining improved finished products via continuous casting that implements two magnetic fields.These fields were realized via two electromagnetic stirring processes implemented in a single process:one in the nozzle and one in the mold.The qualitative effects of applying double electromagnetic stirring (EMS) were verified through numerical simulation of 178 mm × 178 mm square billets exposed to double electromagnetic fields during the continuous casting process.The accuracy of the numerical calculations was verified via physical experiments.In addition,the final simulation results were compared with the intermediate results,to determine the true effects of different EMS on the metal flow in the mold.The results revealed that casting using EMS with different directions of magnetic field in the mold and the nozzle has the best effect on the distribution of the fluid flow and minimal influence on the stability of the meniscus and yields the minimum metal-jet penetration into the mold.
Intermetallic Evolution of Al-Si-Coated Hot Stamping Steel During Modified Electrically Assisted Rapid Heating

Modified electrically assisted (EA) rapid heating of Al-Si-coated hot stamping steel is suggested,and the intermetallic evolution in the coating during heating is experimentally investigated.In the modified EA rapid heating,a continuous electric current for a suitable duration is applied to a specimen to heat it to a temperature slightly below the melting temperature of the coating.The temperature of the specimen is then kept constant for a specified dwell time.The result of the microstructural analysis shows that the modified EA rapid heating could effectively increase the thickness of the intermetallic layer between the coating and steel substrate much faster than conventional furnace heating and induction heating.The effectiveness of EA rapid heating may be due to the athermal effect of the electric current on the mobility of atoms,in addition to the well-known resistance heating effect.EA rapid heating also provides a technical advantage in that partial austenization can be easily achieved by properly placing the electrodes,as demonstrated in the present study.
Airline Partner Selection Optimization Based on an Improved QSI Model

This paper studies airline partner selection.The international airline operation involves considerable cooperations with other airlines at home and abroad.How to choose the most suitable partners is a realistic issue for Chinese airlines.In this paper the quality of service index(QSI)model is improved by applying more necessary indexes based on the analysis of large scale of data.A partner selection model is established to help airlines identify the best partner(s)in a scientific and effective way among potential candidates.Finally,real data from an airline company in China is applied to test the model.The outcome verify the effectiveness of the partner selection model proposed in this paper.The model can be helpful for selecting more suitable partners and increasing coordination value through cooperation with the partners.
Working Mechanism of a Kind of Non-resonant Linear Piezoelectric Motor with Flexible Driving End

A non-resonant piezoelectric linear motor with a flexible driving end,which has an extensive working frequency range and good operation stability,is studied theoretically and experimentally.Based on the microscopic vibration characteristics of the motor stator,the longitudinal vibration model is established for the whole motor system.According to the Coulomb friction model and the motor vibration model,the friction mechanism of the nonresonant piezoelectric linear motor is investigated by dynamical analysis of the whole motor system.Furthermore,the vibration characteristics and mechanical output characteristics of the stator are simulated and experimentally studied on the basis of the friction drive mechanism model.Finally,both the simulation and experimental results show that this kind of motor remain stable in the frequency domain from 2.2kHz to 3.5kHz and that when the pre-stress is 4Nand the driving voltage is 90V,the maximum velocity of the motor is above 4mm/s and the maximum thrust is nearly 0.5N.
Revealing the atomistic deformation mechanisms of face-centered cubic nanocrystalline metals with atomic-scale mechanical microscopy: A review

Nanocrystalline metals have many functional and structural applications due to their excellent mechanical properties compared to their coarse-grained counterparts. The atomic-scale understanding of the deformation mechanisms of nanocrystalline metals is important for designingnewmaterials, novel structures and applications. The review presents recent developments in the methods and techniques for in situ deformation mechanism investigations on face-centered-cubic nanocrystalline metals. In the first part, we will briefly introduce some important techniques that have been used for investigating the deformation behaviors of nanomaterials. Then, the size effects and the plasticity behaviors in nanocrystalline metals are discussed as a basis for comparison with the plasticity in bulk materials. In the last part, we show the atomic-scale and time-resolved dynamic deformation processes of nanocrystalline metals using our in-lab developed deformation device.
Synthesis of porous carbon spheres derived from lignin through a facile method for high performance supercapacitors

Porous carbon spheres (PCS) derived from lignin have been prepared through a facile method and fabricated as electrodes for electric double-layer capacitors. Spherical shaped mixtures of lignosulfonate and crystalized KOH are formed by spray drying of a solution of lignosulfonate and KOH. Activation by KOH is performed at high temperatures along with lignosulfonate carbonization. With an appropriate pore structure, the obtained PCS have a specific surface area of 1372.87m~2 g~(–1) and show a capacitance of 340 F g~(–1) in 3M KOH at a current density of 0.5Ag~(–1). Moreover, a symmetric supercapacitor fabricated using the PCS as electrodes show a maximum capacitance of 68.5 F g~(–1), and an energy density of 9.7Whkg~(–1) at a power density of 250Wkg~(–1). The capacity retention is more than 94.5% after 5000 galvanostatic chargedischarge cycles. The excellent characteristics seem to be ascribed to the pore structures of PCS that have a large specific surface area and a low electrical resistance.
Application of materials based on group VB elements in sodium-ion batteries: A review

Owing to their high redox activity, abundant resource, and low cost, compounds based on group VB elements (V, Nb, and Ta) are promising electrode materials for an array of energy storage devices. Moreover, their open structure benefits transportation and accommodation of alkali Na+ ions, rending them particularly appealing for cost-effective sodium-ion batteries (SIBs). In the last decade, these materials have evoked intensive investigations in SIBs, serving as either cathode, anode, or both depending on their sodiation degree and redox potential. Exciting progress has been made, but significant gaps in our knowledge still remain. Their practical application in SIBs remains unclear and thus calls for further efforts to settle several technical challenges in terms of poor conductivity, unstable cycling, and inefficient charge storage. In this perspective, a brief overview is given of recent progress on how to solve these technical issues and envision their bright future in SIBs, which may serve as a source to inspire researches on relevant topics.
2号染色体父系单亲二倍体遗传亲子鉴定1例

迄今为止,虽然单亲二倍体遗传变异的报道不是很多见,但在亲子鉴定中仍需引起重视,以免造成误判。特别是出现同一染色体上多基因座不符合孟德尔遗传规律,而且突变步骤多(≥3)的案例时,更应引起高度重视。
外伤性鼓膜穿孔愈合后再次穿孔法医学鉴定1例

本例鉴定有两点值得注意之处:(1)外伤性鼓膜穿孔愈合后因炎症再次穿孔。本例的鉴定重点是分析重新鉴定时炎性穿孔与外伤的因果关系。因被鉴定人6月11日伤后首次鉴定时未及时进行颞骨CT检查,其伤前左耳是否存在中耳炎的情况不明确。6月15日耳科检查的图像显示其左耳鼓膜外伤性穿孔未见鼓膜感染的征象。7月5日、26日两次耳科检查的图像显示其左耳鼓膜穿孔已愈合,鼓膜及鼓室内可见炎症征象。8月17日、9月1日耳科检查显示其左耳鼓膜鼓气时有气泡产生,气泡产生的位置符合穿孔的位置。上述情况说明,被鉴定人左耳鼓膜外伤性穿孔愈合期间左耳中耳炎症逐渐进展,但外伤性鼓膜穿孔在6周内已愈合。虽被鉴定人一直住院治疗,但炎症未得到有效控制,重新鉴定时被鉴定人左耳鼓膜情况符合中耳炎造成的鼓膜再次穿孔,本次穿孔与患者住院期间及出院后是否得到有效医疗救治及自身因素(是否配合治疗,是否有其他促发感染的行为)等均有一定的关系,无法明确判断与6月11日外伤的因果关系,故依据《人体损伤程度鉴定标准》,其损伤属于轻微伤。(2)对于声导抗检测结果的重新认识。在以往的实践中,鼓室图检测不到有效的曲线,诊断提示鼓室容积增大,客观说明鼓膜存在穿孔。本例声导抗检测发现鼓室导抗图呈A型、B型曲线的情况下,鼓膜鼓气录像时均可见到气泡产生及破裂,说明鼓膜并非完整。分析其原因,应为鼓膜在检测时已存在炎症的浸润,鼓膜的顺应性下降,且鼓膜表面覆盖有液性分泌物。在做鼓室导抗检测时,鼓膜可以随着外耳压力的改变进行幅度有限的变形,呈现出一定的声顺动态变化,因鼓膜表面覆盖分泌物形成一个相对密闭的表面,所以可以检测到有效的曲线而不提示鼓室容积增大。所以在此种情况下,鼓室图检测不能有效提示鼓膜是否存在穿孔,必须结合鼓膜鼓气时的照相、录像情况综合判断鼓膜是否存在穿孔。
运用电度表运行变化推断案发时间2例

通过上述两起案例,笔者认为:在被害人生活规律的案件中,特别是被害人独居情况下,可优先考虑运用电度表用电量变化推断案发时间。另外,在与电流变化密切相关的死亡案件中,或是案件现场有导致电度表运行变化的因素(如现场电路的切断),用电度表运行变化推断案发时间都有较大的价值。当然,这种案发时间的推断也需要结合案件现场勘验与调查情况,如本文的案例2,现场勘验和调查没有发现影响电度表运行变化的其他因素存在,才使得案发时间的推断更为可靠。
数字化方法复制诊断饰面在重度氟斑牙全冠修复中的应用

重度氟斑牙常累及口内多数牙齿,对前牙美观及后牙咬合功能的恢复提出了更高的要求.上海交通大学医学院附属第九人民医院口腔修复科收治1例重度氟斑牙患者,通过牙体牙髓、牙周科等前期治疗及术前数字化设计,并依靠椅旁计算机辅助设计与辅助制作(computer aided design and computer aided manufacture,CAD/CAM)系统较精确地再现设计方案,进行修复治疗,现报道如下.
A 4H-SiC betavoltaic battery based on a ~(63)Ni source

A 4H-SiC-~(63)Ni p-n-junction-based betavoltaic battery is investigated.The Monte Carlo method is used to simulate the self-absorption effect of the ~(63)Ni source,the backscattering process,and the transport of beta particles in 4H-SiC material.The main factors that affect the energy conversion efficiencies of the cell are analyzed.Based on the simulation results,it can be calculated that,when the thickness of the 63Ni source increases from 2×10~(-3) to 10 lm,the theoretical maximum device conversion efficiency increases from 16.77 to 23:51% and the total conversion efficiency decreases from 16.73 to 1:48%.Furthermore,a feasible design with a maximum output power density of 0:36 μW/cm~2 and an optimal device conversion efficiency of 23:5% is obtained.