BMS电路板多模块协同热-力耦合建模及仿真分析

针对现有电动汽车电池管理系统(BMS)电路板研究仅仅考虑单一功能模块的温度场及其散热效果,缺乏考虑BMS多个功能模块在温度场和力场下的相互影响及协同效应的研究的情况,以某商用BMS电路板为研究对象,采用ANSYS构建了表征BMS多模块协同作用下的热-力耦合数值仿真分析模型并验证了其有效性.在此基础上,针对BMS电路板各功能模块温度场及热变形行为开展了数值仿真研究.结果表明:BMS电路板温度分布不均,最大温差达20.5℃.均衡模块存在积热,温度高达54.4℃.高温导致电路板组件发生热膨胀变形,同时电路板约束诱发均衡模块及供电模块边缘的贴片电阻出现热应力集中,两者共同作用致使BMS均衡模块、供电模块产生凸起翘曲变形,且Z轴热变形量随着温度升高而增大,最大变形量达9.5μm,应针对BMS电路板上积热模块开展散热优化设计.

基于共轭梯度法的晶闸管电热耦合模型快速求解方法研究

为解决传统求解技术在处理效率和计算成本上的局限问题,针对晶闸管电热应力耦合交互模型,提出一种基于共轭梯度法的高效解析方法。通过优化迭代过程和收敛条件来显著提升求解效率和精度。新的参数选择策略被引入以自动调整算法迭代步长,加快收敛速度,减少计算资源消耗。相比传统求解方法,所提优化方法在求解时间上平均减少10%,求解精度提高8%。这一进展证明自适应共轭梯度法在电热应力耦合模型快速求解中的有效性,可为电力电子设备热管理提供高效、可靠的计算工具。所提方法在多种测试条件下均表现出显著的提升效率和良好的精确度,为晶闸管电热耦合模型的高效求解提供了创新方案,同时对电力电子领域的相关研究具有重要的实践意义。

液氧液甲烷同温共底贮存瞬态热力特性仿真研究

针对大面积冷屏保护下的液氧/液甲烷同温共底贮箱,建立了耦合真空多层绝热与主动制冷系统的瞬态传热模型,研究了液氧/液甲烷共底自增压与零蒸发贮存过程中贮箱外部绝热结构与内部气液相的热力参数变化规律,讨论了共底夹层采用不具有绝热能力的材料对液氧/液甲烷共底零蒸发贮存特性的影响。研究结果表明,在适当的冷量输入条件下,大面积冷屏方案可以实现外界漏热的有效阻挡;采用铝合金共底夹层有利于稳定液氧和液甲烷的共底贮存状态,使液氧/液甲烷在20 h内快速达到热平衡;在零蒸发贮存周期内,液氧/液甲烷共底贮存温度波动小于0.2 K,压力波动小于2.46 kPa且具有抗热扰动的能力。

稀土Gd对Ni-Cr-Mo合金热变形行为的影响

含Gd镍铬钼合金作为乏燃料贮运用中子屏蔽材料具有广阔的应用前景,却在热加工时极易发生开裂,为了优化合金热变形工艺参数,本文以Ni-Cr-Mo合金为研究对象,研究了Gd加入后引起的组织变化。在变形温度为1 000~1 200℃、应变速率为0.01~5 s^(-1)条件下进行等温热压缩实验,计算合金相关材料常数及热变形激活能,构建热加工图并确定热加工窗口,结合微观组织进行分析,研究Gd对合金热变形行为的影响。结果表明,Ni-Cr-Mo合金中加入了1.2%的Gd,合金的变形激活能从472.15 kJ/mol降至422.9 kJ/mol,在热变形时合金的能量消耗效率更高,组织演变更充分,塑性失稳区域由高温向低温逐渐转移,并且增大了合金在1 000~1 060℃,0.01~0.32 s^(-1)低温低应变速率下安全区的面积。合金最佳热加工区间为:0.5真应变量,温度(T)为1 113~1 164℃,应变速率(ε)为0.01~0.2 s^(-1)。Gd在晶界或枝晶间以金属间化合物GdNi_(5)析出,GdNi_(5)相作为硬脆相,在热变形过程中其周围产生较大应变,导致组织中畸变能更高,从而促进周围变形晶粒发生再结晶,降低组织中的残余应变。

藏文■词义演变与元代蒙、藏文化交流

文章通过对藏文文献中“■”(史册)及相关词汇意涵和形成年代的梳理,对比蒙古文等多语种文献中“debter”等词汇之含义,认为藏文“■”一词大约出现于14世纪的藏文历史文献中,并且经历了从“■”到“■”的书写形态的变化过程。其内涵则渊源于13世纪的蒙古词汇“debter”,不仅具有册子、账本、文件等意义,而且还用以指代史册、史籍等。“■”一词的词义演变过程,及其与蒙古文相关词汇语义之关联,体现了蒙古文化因素对于藏文历史写作和文化观念的强烈影响,是13世纪中叶以后西藏地方与蒙古及元朝中央在政治、历史文化关系方面的一种现实写照和重要表征。

白葡奈氏菌片联合布地奈德雾化吸入治疗小儿急性肺炎的临床疗效

目的 探究白葡奈氏菌片联合布地奈德雾化治疗小儿急性肺炎(AP)的临床疗效。方法 选取2021年2月至2023年2月界首市人民医院收治的92例AP患儿,采用随机数字表法将其分为观察组与对照组,每组各46例,对照组在常规治疗的基础上给予安慰剂治疗,观察组在常规治疗的基础上口服白葡奈氏菌片。治疗5 d后评估两组患儿疗效,酶联免疫法检测血清炎症因子水平,流式细胞法检测免疫功能水平,脉冲震荡肺功能仪检测患儿呼吸力学指标,并观察治疗方案的安全性。结果 与对照组相比,观察组总有效率(78.26%vs. 95.65%)升高(P<0.05);观察组治疗后肿瘤坏死因子-α(TNF-α)水平低于对照组[(16.02±2.54) ng/L vs.(18.47±2.39) ng/L],白细胞介素-10(IL-10)水平也低于对照组[(105.68±12.59) ng/L vs.(146.92±17.33) ng/L],干扰素-γ(IFN-γ)水平高于对照组[(189.76±24.59) ng/L vs.(161.40±20.76) ng/L](P<0.05);两组患儿治疗后CD3^(+)、CD4^(+)及CD4^(+)/CD8^(+)水平均升高,观察组各免疫指标优于对照组(P<0.05);两组患儿治疗后5 Hz时气道阻力(R5)、共振频率(Fres)均降低,总顺应性(Ct)升高(P<0.05);观察组各项呼吸力学指标优于对照组(P<0.05);观察组退热时间、咳嗽消失时间、肺啰音消失时间及住院时间均短于对照组(P<0.05);两组患儿治疗期间均未见明显的不良反应。结论 白葡奈氏菌片联合雾化治疗能够提高AP患儿的疗效,减轻机体炎症反应,提高患儿呼吸功能及免疫功能,加速改善临床症状,且安全性较高。

壮医莲花针拔罐逐瘀疗法治疗风痰瘀阻型缺血性中风恢复期的临床效果

目的 探讨壮医莲花针拔罐逐瘀疗法治疗风痰瘀阻型缺血性中风恢复期的临床效果。方法 选取2023年1月至10月广西国际壮医医院风痰瘀阻型缺血性中风恢复期的72例患者,按照随机数字表法将其分为治疗组与对照组,每组36例。对照组采用基础治疗,治疗组在对照组基础上,增加壮医莲花针叩刺、刺拔、吸附。两组均治疗28 d。比较两组的临床效果和治疗前、治疗14 d后、治疗28 d后的中医证候积分、日常生活活动(ADL)量表评分、生活质量评分、美国国立卫生研究院卒中量表(NIHSS)评分。结果 治疗组临床疗效优于对照组(P<0.05)。整体分析发现:中医症候评分组间比较、时间点比较及交互作用差异均有统计学意义(P<0.05)。NIHSS、ADL、生活质量评分组间比较、时间点比较差异均有统计学意义(P<0.05)。组内比较:治疗14、28 d后两组中医症候、NIHSS评分均低于治疗前,治疗28 d后两组中医症候、NIHSS评分均低于治疗14 d后;治疗14、28 d后两组ADL、生活质量评分均高于治疗前,治疗28 d后两组ADL、生活质量评分均高于治疗14 d后(P<0.05)。组间比较:治疗14、28 d后治疗组中医症候、NIHSS评分低于同期对照组,ADL、生活质量评分均高于同期对照组(P<0.05)。结论 壮医莲花针拔罐逐瘀疗法是治疗风痰瘀阻型缺血性中风恢复期患者的一种有效方法,可改善神经功能缺损、提高日常生活活动能力。

《金册》成书过程初探

《金册》成书于清末,是由蒙古族学者扎瓦达木丁以《音韵》为基础而撰写的蒙古佛教史,全称《瞻部洲北方蒙古族历史·神奇金册》,其中诸多篇章叙述了西北少数民族区域文化及与中原文化“交往交流交融”的历史实事。其后序记载编撰时间历经14年之久,取材涉及汉、藏、蒙、满等多语种历史文献资料。经研究发现,《金册》成书可分四个阶段,即夸语种搜集文献资料;翻译资料,以《音韵》为基础而创作阶段;《金册》成书;后期补充完善。《金册》的取材和编撰过程极大地体现了此书不同于以往的蒙藏教法史,具有极大的研究价值。

CXC chemokines and chemokine receptors in gastric cancer: From basic findings towards therapeutic targeting

Gastric cancer is the fourth most common cancer,and the second-highest cause of cancer-related deaths worldwide.Despite extensive research to identify novel diagnostic and therapeutic agents,patients with advanced gastric cancer suffer from a poor quality of life and poor prognosis,and treatment is dependent mainly on conventional cytotoxic chemotherapy.To improve the quality of life and survival of gastric cancer patients,a better understanding of the underlying molecular pathologies,and their application towards the development of novel targeted therapies,is urgently needed.Chemokines are a group of small proteins associated with cytoskeletal rearrangements,the directional migration of several cell types during development and physiology,and the host immune response via interactions with G-protein coupled receptors.There is also growing evidence to suggest that chemokines not only play a role in the immune system,but are also involved in the development and progression of tumors.In gastric cancer,CXC chemokines and chemokine receptors regulate the trafficking of cells in and out of the tumor microenvironment.CXC chemokines and their receptors can also directly influence tumorigenesis by modulating tumor transformation,survival,growth,invasion and metastasis,as well as indirectly by regulating angiogenesis,and tumor-leukocyte interactions.In this review,we will focus on the roles of CXC chemokines and their receptors in the development,progression,and metastasis of gastric tumors,and discuss their therapeutic potential for gastric cancer.

Simultaneous modulated accelerated radiation therapy for esophageal cancer:A feasibility study

AIM:To establish the feasibility of simultaneous modulated accelerated radiation therapy(SMART) in esophageal cancer(EC).METHODS:Computed tomography(CT)datasets of 10patients with upper or middle thoracic squamous cell EC undergoing chemoradiotherapy were used to generate SMART,conventionally-fractionated three-dimensional conformal radiotherapy(3DCRT)and intensity-modulated radiation therapy(cf-IMRT)plans,respectively.The gross target volume(GTV)of the esophagus,positive regional lymph nodes(LN),and suspected lymph nodes(LN±)were contoured for each patient.The clinical target volume(CTV)was delineated with 2-cm longitudinal and 0.5-to 1.0-cm radial margins with respect to the GTV and with 0.5-cm uniform margins for LN and LN(±).For the SMART plans,there were two planning target volumes(PTVs):PTV66=(GTV+LN)+0.5 cm and PTV54=CTV+0.5 cm.For the 3DCRT and cfIMRT plans,there was only a single PTV:PTV60=CTV+0.5 cm.The prescribed dose for the SMART plans was 66 Gy/30 F to PTV66 and 54 Gy/30 F to PTV54.The dose prescription to the PTV60 for both the 3DCRT and cf-IMRT plans was set to 60 Gy/30 F.All the plans were generated on the Eclipse 10.0 treatment planning system.Fulfillment of the dose criteria for the PTVs received the highest priority,followed by the spinal cord,heart,and lungs.The dose-volume histograms were compared.RESULTS:Clinically acceptable plans were achieved for all the SMART,cf-IMRT,and 3DCRT plans.Compared with the 3DCRT plans,the SMART plans increased the dose delivered to the primary tumor(66Gy vs 60 Gy),with improved sparing of normal tissues in all patients.The Dmax of the spinal cord,V20 of the lungs,and Dmean and V50 of the heart for the SMART and 3DCRT plans were as follows:38.5±2.0 vs 44.7±0.8(P=0.002),17.1±4.0 vs 25.8±5.0(P=0.000),14.4±7.5 vs 21.4±11.1(P=0.000),and 4.9±3.4vs 12.9±7.6(P=0.000),respectively.In contrast to the cf-IMRT plans,the SMART plans permitted a simultaneous dose escalation(6 Gy)to the primary tumor while demonstrating a significant trend of a lower irradiation dose to all organs at risk except the spinal cord,for which no significant difference was found.CONCLUSION:SMART offers the potential for a 6Gy simultaneous escalation in the irradiation dose delivered to the primary tumor of EC and improves the sparing of normal tissues.

Effects of oral tacrolimus as a rapid induction therapy in ulcerative colitis

AIM:To determine the efficacy and safety of rapid induction therapy with oral tacrolimus without a meal in steroid-refractory ulcerative colitis(UC)patients.METHODS:This was a prospective,multicenter,observational study.Between May 2010 and August 2012,49 steroid-refractory UC patients(55 flare-ups)were consecutively enrolled.All patients were treated with oral tacrolimus without a meal at an initial dose of 0.1mg/kg per day.The dose was adjusted to maintain trough whole-blood levels of 10-15 ng/m L for the first 2 wk.Induction of remission at 2 and 4 wk after tacrolimus treatment initiation was evaluated using Lichtiger’s clinical activity index(CAI).RESULTS:The mean CAI was 12.6±3.6 at onset.Within the first 7 d,93.5%of patients maintained high trough levels(10-15 ng/m L).The CAI significantly decreased beginning 2 d after treatment initiation.At 2wk,73.1%of patients experienced clinical responses.After tacrolimus initiation,31.4%and 75.6%of patients achieved clinical remission at 2 and 4 wk,respectively.Treatment was well tolerated.CONCLUSION:Rapid induction therapy with oral tacrolimus shortened the time to achievement of appropriate trough levels and demonstrated a high remission rate 28 d after treatment initiation.Rapid induction therapy with oral tacrolimus appears to be a useful therapy for the treatment of refractory UC.

Hybrid vs sequential therapy for eradication of Helicobacter pylori in Taiwan: a prospective randomized trial

AIM: To evaluate the efficacy of sequential vs hybrid therapy in patients with Helicobacter pylori(H. pylori) infection.METHODS: From March 2013 to May 2014,one hundred and seventy-five H. pylori infected patients who had not been treated for H. pylori before wererandomized to receive either sequential therapy(rabeprazole 20 mg and amoxicillin 1 g twice daily for 5 d,followed by rabeprazole 20 mg,clarithromycin 500 mg and metronidazole 500 mg twice daily for 5 d) or hybrid therapy(rabeprazole 20 mg and amoxicillin 1 g for 7 d,followed by rabeprazole 20 mg,amoxicillin 1 g,clarithromycin 500 mg and metronidazole 500 mg twice daily for 7 d). H. pylori status was confirmed by positive results of both rapid urease test and histology examination or a positive result of culture. Eradication efficacy was assessed by follow-up endoscopy with rapid urease test and histological examination 8 wk after the end of anti-H. pylori therapy,or 13C-urea breath test at least 4 wk after completion of treatment. The primary outcome was H. pylori eradication by intension-to-treat(ITT) and per-protocol(PP) analyses.RESULTS: One hundred and sixty-seven patients(83 patients in the sequential group and 84 patients in the hybrid group) completed the study. The compliance rates were 97.6% and 97.7% for the two groups,respectively. The eradication rate was 78.2% for the sequential group and 92% for the hybrid group by ITT analysis(P = 0.01). The eradication rate was 81.9% for the sequential group and 96.4% for the hybrid group by PP analysis(P = 0.01). Univariate analysis for the clinical and bacterial factors did not identify any risk factors associated with treatment failure. Severe adverse events were observed in 2.3% of patients in the sequential group and 2.4% of those in the hybrid group.CONCLUSION: Due to a grade A(> 95%) success rate for H. pylori eradication by PP analysis,similar compliance and adverse events,hybrid therapy seems to be an appropriate eradication regimen in Taiwan.

Thermal Fatigue Behaviour of Co-Based Alloy Coating Obtained by Laser Surface Melt-Casting on High Temperature Alloy

A thermal fatigue behaviour of Co-based alloy coating obtained by laser surface meltcasting on the high temperature alloy GH33 was studied.The results show that after each time of thermal cycling,the final residual stress was formed in the melt-casting layer which is attributed to the thermal stress and structural stress.Through the first 50 times of thermal cycling,the morphology of coating still inherits the laser casting one,but the dendrites get bigger;After the second 50 times of thermal cycling,corrosion pits emerge from coating,and mostly in the places where coating and substrate meet.The fatigue damage type of coating belongs to stress corrosion.

Frequency and prognostic role of mucosal healing in patients with Crohn's disease and ulcerative colitis after one-year of biological therapy

AIM:To assess the endoscopic activity before and after a one-year period of biological therapy and to evaluate the frequency of relapses and need for retreatment after stopping the biologicals in patients with Crohn’s disease(CD)and ulcerative colitis(UC).METHODS:The data from 41 patients with CD and 22 patients with UC were assessed.Twenty-four CD patients received infliximab,and 17 received adalimumab.The endoscopic severity of CD was quantified with the simplified endoscopic activity score for Crohn’s disease in CD and with the Mayo endoscopic subscore in UC.RESULTS:Mucosal healing was achieved in 23 CD and7 UC patients.Biological therapy had to be restarted in78%of patients achieving complete mucosal healing with CD and in 100%of patients with UC.Neither clinical remission nor mucosal healing was associated with the time to restarting the biological therapy in either CD or UC.CONCLUSION:Mucosal healing did not predict sustained clinical remission in patients in whom the biological therapies had been stopped.

SYNTHESIS AND THERMAL STABILITY OF NANOCOMPOSITE nc-TiN/a-TiB_2 THIN FILMS

Several nc-TiN/a-TiB2 thin films comprised of nanocrystalline (nc-) TiN and amor phous (a-) TiB2 phases were deposited on Si(100) at room temperature by reactive unbalanced dc magnetron sputtering, followed by vacuum annealed at 400, 600, 80 0 and 1000℃ for 1h, respectively. Effects of B content on microstructure, mecha nical behaviors and thermal microstructure stability have been investigated by X -ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and nanoindentation measurements. The results indicated that B addition greatly affected both microstructure and mechanical behavior of nc-Ti N/a-TiB2 thin films. With increasing B content the grain size decreased. A maxim um hardness value of about 33GPa was obtained at B content of about 19at.%. The improved mechanical properties of nc-TiN/a-TiB2 films with the addition of B int o TiN were attributed to their densified microstructure with development of fine grain size. Only addition of sufficient B could restrain grain growth during an nealing. High B content resulted in high microstructure stability. The crystalli zation of amorphous matrix occurred at about 800℃, forming TiB or TiB2 crystall ite, depending on B content. Before that no change in bonding configuration was found.

THERMAL DECOMPOSITION BEHAVIOR OF AMMONIUM THIO TUNGSTATE in H_2

The ther m al deco m position mechanism of a m m oniu m thiotungstate of the size of 63 ～75 μmin H2 has been investigated by D T A and X R D methods . The ther m al deco m position activationenergies and the orders of a m m oniu m thiotu ngstate were calculated by means of Kissinger , Freem an Carroll and Coast Redfern m ethods . It w as also obtained that therm al deco m posi tion is cond ucted according to four reaction equations :( N H4) 2 W S4· H2 O(s) ( N H4) 2 W S4(s) + H2 O(g) W S2(s) + 2 N H3(g) + H2(g) + 2 S(s) + H2 O(g) W S2(s) + 2 N H3(g) + 2 H2 S(g) + H2 O(g) W S2(s) + W(s) + 2 N H3(g) + 2 H2 S(g) + H2 O(g) .

Nanoscale mass sensing based on vibration of single-layered graphene sheet in thermal environments

Based on vibration analysis, single-layered graphene sheet （SLGS） with multiple attached nanoparticles is developed as nanoscale mass sensor in thermal environments. Graphene sensors are assumed to be in simplysupported configuration. Based on the nonlocal plate the- ory which incorporates size effects into the classical theory, closed-form expressions lot the frequencies and relative fre- quency shills of SLGS-based mass sensor are derived using the Galerkin method. The suggested model is justified by a good agreement between the results given by the present model and available data in literature. The effects of tem- perature difference, nonlocal parameter, the location of the nanoparticle and the number of nanoparticles on the relative frequency shift of the mass sensor are also elucidated. The obtained results show that the sensitivity of the SLGS- based mass sensor increases with increasing temperature difference.

On stability of elastic domain during isothermal solid-solid phase transformationin a tube configuration

Under isothermal quasi-static stretching the phase transition of a superelastic NiTi tube involves the formation （during loading） and vanishing （in unloading） of a high strain （martensite） domain. The two events are accompanied by a rapid stress drop/rise due to the formation/vanishing of do- main fronts. From a thermodynamic point of view, both are instability phenomena that occur once the system reaches its critical state. This paper investigates the stability of a shrink- ing cylindrical domain in a tube configuration during unload- ing. The energetics and thermodynamic driving force of the cylindrical domain are quantified by using an elastic inclu- sion model. It is demonstrated that the two domain fronts ex- hibit strong interaction when they come close to each other, which brings a peak in the total energy and a sign change in the thermodynamic driving force. It is proved that such domain front interaction plays an important role in control- ling the stability of the domain and in the occurrence of stress jumps during domain vanishing. It is also shown that the pro- cess is governed by two nondimensional length scales （the normalized tube length and normalized wall-thickness） and that the length scale dependence of the critical domain length and stress jump for the domain vanishing can be quantified by the elastic inclusion model.

Thermo-mechanical Properties of In-situ Formed Al_2O_3-SiC-SiAION Composites

Al2 O3 - SiC - SiAION composite specimens have been prepared using fused alumina, ultra fine α-Al2O3, Si and Al powders as starting materials and liquid phenol formaldehyde resin as binder and firing at 1 500 ℃ for 3 h in carbon embedded condition. Thermo-mechanical properties of Al2 O3 - SiC - SiAlON composites have been studied. The results show ： （ 1 ） Al2 O3 - SiC - SiAION composites can be prepared and sintered at 1 500 ℃ under carbon embedded condition. When Si/Al ratio is 8/0 and 7/1, the prepared composite is Al2O3 - SiC - O＇ -SiAlON; when Si/Al ratio is 5/3 and 3/5, the pre- pared composite is Al2 O3 - SiC - β-SiAION. （ 2 ） The composites possess high temperature strength properties. Hot modulus of rupture at 1 400 ℃ is 10 - 30 MPa. They are in elastic range up to 1 000 ℃, after which plastic deformation is observed; even at 1 400 ℃, amount of deformation is relatively low. （3） The com- posites possess good thermal shock resistance, their resid- ual strength ratio （AT = 1 100 ℃ ） is 65% - 80%. （4） The marked improvement in thermo-mechanical properties of Al2O3 - SiC - SiAlON composites may be at- tributed to the in-situ formation of SiC, SiAlON and AIN, the fibrous SiC, columnar SiAlON and tabular-like AlN fill in the corundum skeleton structure creating strengthening and toughening effects.