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基于混沌遗传算法的圆度误差测量

计量学报 2009年第6期30卷 -页

作者：王伯平王薇孙大刚阎献国都丽娜 Bo-ping da-gang Xian-guo li-na 太原科技大学山西太原030024 太原高新技术开发区山西太原030006

提出了一种基于混沌遗传算法的计算圆度误差的新方法.它利用混沌优化方法的遍历性和随机性,通过混沌扰动操作可克服传统遗传算法中的早熟问题,确保算法的全局收敛性.该方法满足最小条件原理,其计算结果的精确度非常高,理论上可以获得全... 详细信息

提出了一种基于混沌遗传算法的计算圆度误差的新方法.它利用混沌优化方法的遍历性和随机性,通过混沌扰动操作可克服传统遗传算法中的早熟问题,确保算法的全局收敛性.该方法满足最小条件原理,其计算结果的精确度非常高,理论上可以获得全局最优解.实例计算表明,这种算法简单明确,具有精度高、收敛速度快、易于计算机程序实现和推广应用等特点.Abstract：A new method for calculating the roundness error based on chaos genetic algorithms is proposed. The system utilizes the ergodicity and randomness of chaos optimal method and by means of chaos stir operation, which can overcame the problem of premature convergence in traditional genetic algorithms and ensured an convergence of the algorithms. The method satisfies the principle of the least condition, the precision of calculating result is very high and can find .the global optimal solution. An actual calculated example showed that this method is simple and clear and it has features of high precision and fast convergent speed as well as using computer easily and popularizing application easily.

关键词：混沌遗传算法圆度误差测量 Genetic Algorithms Based Roundness Error genetic algorithms premature convergence 计算结果 roundness error high precision 混沌优化方法传统遗传算法 traditional application 全局最优解全局收敛性 new method operation 最小条件推广应用

Micro-strain regulation strategy to stabilize perovskite lattice based on the categories and impact of strain on perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 578-604页

作者： Caixia li Wenwu liu Shiji da lingbin Kong Fen Ran State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology

Photovoltaic metal halide perovskite solar cells(PSCs) convert light to electricity more efficiently than crystalline silicon cells, and the cost of materials used to make them is lower than that of silicon *** efficiency is not a core issue affecting the application of perovskite solar cells in special *** present, stability is the major technical encounters that hinders its further commercial development. Microstrain in PSCs is currently a significant factor responsible for the device's instability. Strain-induced ion migration is widely believed to accelerate perovskite degradation even when external stimuli are ***, it is imperative to study strain to enhance the stability of PSCs. This paper reviews recent developments to understand strain's origin and effect mechanisms on performance of PSCs, including ion migration,failure behavior, defect formation, and its effect on photoelectric properties, stability, and ***, several well-known strain management strategies are systematically introduced based on the strain effect mechanism and strain engineering on the film, providing more clues for further preparation with increased stability. The manipulation of external physical strain applied from films to entire devices has been extensively studied. Furthermore, recommendations for future research directions and chemical approaches have been provided. It is emphasized that strain engineering plays a crucial role in improving the efficiency and longevity of PSCs. Tensile strain causes rapid degradation, while moderate compressive strain and external strain control could improve properties and stability. Efforts should focus on controlling compressive strain to mitigate residual tensile strain and introducing it in a controlled manner. Future research endeavors may focus on exploring these pathways to improve the efficiency and lifespan of PSCs.

关键词： Halide perovskite solar cells Strain origins Strain effects Strain management

PAMPS/SiO_2杂化水凝胶的合成及电场敏感性研究

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高分子学报 2012年第7期22卷 728-734页

作者：李云龙林松柏张青海李大刚黎明职业大学轻纺工程系实用化工材料福建省高校应用技术工程中心泉州362000

以2-丙烯酰胺-2-甲基丙磺酸(AMPS)为有机原料,正硅酸乙酯(TEOS)为无机原料,过硫酸钾为引发剂,N,N'-亚甲基双丙烯酰胺为交联剂,通过原位-凝胶水溶液聚合法合成了一系列不同二氧化硅含量和不同聚离子浓度的聚(2-丙烯酰胺-2-甲基丙磺酸)/... 详细信息

以2-丙烯酰胺-2-甲基丙磺酸(AMPS)为有机原料,正硅酸乙酯(TEOS)为无机原料,过硫酸钾为引发剂,N,N'-亚甲基双丙烯酰胺为交联剂,通过原位-凝胶水溶液聚合法合成了一系列不同二氧化硅含量和不同聚离子浓度的聚(2-丙烯酰胺-2-甲基丙磺酸)/二氧化硅杂化电场敏感性水凝胶.通过扫描电子显微镜(SEM)表征凝胶的结构,研究水凝胶在去离子水以及氯化钠溶液中的溶胀和消溶胀行为.结果表明,系列凝胶的平衡溶胀度介于224.9至325.6之间,复合凝胶的溶胀速率随TEOS用量的增加而降低;除理想杂化凝胶外,随着聚离子浓度的升高,凝胶在氯化钠溶液中的消溶胀速率逐渐减小.对凝胶的电场敏感性研究表明,当聚离子浓度大于氯化钠溶液浓度时,凝胶进一步溶胀,反之则消溶胀,其中杂化凝胶的再溶胀性能减弱,而消溶胀行为变得更为明显.同时制得的理想杂化凝胶,较纯有机凝胶具有更为理想的力学性能,最大抗压缩强度可达23.4 MPa.

关键词：水凝胶电场敏感 2-丙烯酰胺-2-甲基丙磺酸二氧化硅

Recovery of high purity silicon from SoG crystalline silicon cutting slurry waste

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Transactions of Nonferrous Metals Society of China 2014年第4期24卷 1237-1241页

作者：李大刚邢鹏飞庄艳歆李峰涂赣峰东北大学材料与冶金学院沈阳110819 东北大学材料电磁过程教育部重点实验室沈阳110819

The composition and size distribution of cutting waste were characterized. The Si-rich powders were obtained from the cutting waste using a physical sedimentation process, and then further purified by removing impurity using acid leaching. The effects of process parameters such as acid leaching time, temperature and the ratio of solid to liquid on the purification efficiency were investigated, and the parameters were optimized. Afterwards, the high-purity Si ingot was obtained by melting the Si-rich powders in vacuum furnace. Finally, the high purity Si with 99.96%Si, 1.1×10^-6 boron （B）, and 4.0×10^-6 phosphorus （P） were obtained. The results indicate that it is feasible to extract high-purity Si, and further produce SoG-Si from the cutting slurry waste.

关键词： SoG-Si cutting slurry waste high-purity Si recovery physical sedimentation high temperature melting

Removal of phosphorus from metallurgical grade silicon by Ar-H_2O gas mixtures

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Transactions of Nonferrous Metals Society of China 2013年第11期23卷 3470-3475页

作者：李峰邢鹏飞李大纲庄艳歆涂赣峰东北大学材料与冶金学院沈阳110004

The removal of phosphorus in metallurgical grade silicon （MG-Si） by water vapor carried with high purity argon was examined. The effect of the nozzle types, refining time, refining temperature, refining gas temperature and refining gas flow rate on the phosphorus removed was investigated by the self-designed gas blowing device. The optimal refining conditions are nozzle type of holes at bottom and side, refining time of 3 h, refining temperature of 1793 K, refining gas temperature of 373 K, refining gas flow rate of 2 L/min. Under these optimal conditions, the phosphorus content in MG-Si is reduced from 94×10^-6 initially to 11×10-6 （mass fraction）, which indicates that gas blowing refining is very effective to remove phosphorus in MG-Si.

关键词： metallurgical grade silicon gas blowing phosphorus thermodynamics

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： da Wan Shuwei Tang Shulin Bai Xiaodong li Peng Ai Wanrong Guo Tuo Zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

乌司他丁通过干预p38MAPK/ERK信号通路减轻脓毒症性肺损伤

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中国药理学通报 2016年第9期32卷 1311-1316页

作者：张利鹏赵焱刘国娟杨大刚周丽华内蒙古医科大学附属医院重症医学科内蒙古呼和浩特010050 内蒙古自治区人民医院神经内科内蒙古呼和浩特010051

目的探讨乌司他丁(ulinastatin,UTI)对脓毒症性急性呼吸窘迫综合征(acute respiratory distress syndrome,ARDS)大鼠的肺保护作用及可能机制。方法 56只Wistar大鼠按随机数字表法分为对照组、模型(LPS 6、12、24 h)组、乌司他丁(UTI 6... 详细信息

目的探讨乌司他丁(ulinastatin,UTI)对脓毒症性急性呼吸窘迫综合征(acute respiratory distress syndrome,ARDS)大鼠的肺保护作用及可能机制。方法 56只Wistar大鼠按随机数字表法分为对照组、模型(LPS 6、12、24 h)组、乌司他丁(UTI 6、12、24 h)组,每组8只。采用腹腔注射细菌脂多糖(lipopolysaccharide,LPS,10 mg·kg^(-1))的方法制备大鼠ARDS模型,乌司他丁组在左侧腹腔注射LPS后1 h后,在右侧腹腔注射乌司他丁20 000 U·kg^(-1),对照组、注射同等剂量的生理盐水,各组大鼠在不同时间点留取肺组织及血浆标本。计算肺组织湿/干质量(W/D)比值;光镜下观察肺组织病理改变;用EliSA法检测各组血浆中肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素^(-1)8(interleukin^(-1)8,IL^(-1)8)、肺表面活性物质A((surfactant protein A,SPA)含量,检测各组肺匀浆中丙二醛(malondialdehyde,Mda)、超氧化物歧化酶(superoxide Dismutase,SOD)和一氧化氮(nitric oxide,NO)含量;免疫组化法检测p38丝裂原活化蛋白激酶(mitogen activated protein kinase,p38MAPK)、细胞外信号调节蛋白激酶(extracellular-signal regulated protein kinase,ERK)蛋白表达情况;Western blot法检测肺组织中磷酸化p38MAPK(p-p38MAPK)及磷酸化ERK(p-ERK)蛋白表达的变化。结果光镜下观察对照组肺组织结构完整,肺泡腔清晰;LPS组肺泡壁增厚,渗出明显,肺组织出现损伤性变化,以12h组变化最明显;UTI组各组病理改变较LPS组明显减轻。与对照组比较,LPS组W/D比值、血浆TNF-α、IL^(-1)8含量,肺匀浆Mda、NO含量均明显升高(Pda含量均明显降低,而肺匀浆SOD含量明显增高,差异有统计学意义;免疫组化结果显示:与对照组比较,LPS组p38MAPK、ERK蛋白在胞质和胞核表达均明显增加,而UTI组较LPS组表达均明显减少;Western blot检测结果显示:与对照组比较,LPS组肺组织p-p38MAPK/ERK蛋白表达均明显增高,而UTI干预组蛋白表达均明显受抑制。结论乌司他丁通过干预p38MAPK/ERK信号通路、抗氧化作用而减轻炎症反应,发挥对LPS致脓毒性大鼠ARDS的保护作用。

关键词：乌司他丁细菌脂多糖急性呼吸窘迫综合征 p38丝裂原活化蛋白激酶细胞外信号调节蛋白激酶减轻

Small extracellular vesicles derived from cerebral endothelial cells with elevated microRNA 27a promote ischemic stroke recovery

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Neural Regeneration Research 2025年第1期20卷 224-233页

作者： Yi Zhang Zhongwu liu Michael Chopp Michael Millman Yanfeng li Pasquale Cepparulo Amy Kemper Chao li li Zhang Zheng gang Zhang Department of Neurology Henry Ford HospitalDetroitMIUSA Department of Physics Oakland UniversityRochesterMIUSA Department of Pathology Henry Ford HospitalDetroitMIUSA Division of Pharmacology Department of NeuroscienceReproductive and Dentistry SciencesSchool of MedicineUniversity of Naples“Federico Ⅱ”NaplesItaly

Axonal remodeling is a critical aspect of ischemic brain repair processes and contributes to spontaneous functional *** previous in vitro study demonstrated that exosomes/small extracellular vesicles(sEVs)isolated from cerebral endothelial cells(CEC-sEVs)of ischemic brain promote axonal growth of embryonic cortical neurons and that microRNA 27a(miR-27a)is an elevated miRNA in ischemic *** the present study,we investigated whether normal CEC-sEVs engineered to enrich their levels of miR-27a(27a-sEVs)further enhance axonal growth and improve neurological outcomes after ischemic stroke when compared with treatment with non-engineered CEC-sEVs.27a-sEVs were isolated from the conditioned medium of healthy mouse CECs transfected with a lentiviral miR-27a expression *** EVs isolated from CECs transfected with a scramble vector(Scra-sEVs)were used as a *** male mice were subjected to permanent middle cerebral artery occlusion and then were randomly treated with 27a-sEVs or *** array of behavior assays was used to measure neurological *** with treatment of ischemic stroke with Scra-sEVs,treatment with 27a-sEVs significantly augmented axons and spines in the peri-infarct zone and in the corticospinal tract of the spinal grey matter of the denervated side,and significantly improved neurological *** vitro studies demonstrated that CEC-sEVs carrying reduced miR-27a abolished 27a-sEV-augmented axonal *** analysis revealed that 27a-sEVs systemically administered preferentially localized to the pre-synaptic active zone,while quantitative reverse transcription-polymerase chain reaction and Western Blot analysis showed elevated miR-27a,and reduced axonal inhibitory proteins Semaphorin 6A and Ras Homolog Family Member A in the peri-infarct *** of the Clathrin-dependent endocytosis pathway substantially reduced neuronal internalization of *** data provide evidence that 27a-sEVs have

关键词： axonal remodeling cerebral endothelial cells exosomes miR-27a mitochondria Semaphorin 6A small extracellular vesicles stroke

Mutual regulation of microglia and astrocytes after Gas6 inhibits spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 557-573页

作者： Jiewen Chen Xiaolin Zeng Le Wang Wenwu Zhang gang li Xing Cheng Peiqiang Su Yong Wan Xiang li Department of Spine Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Guangdong Province Key Laboratory of Orthopedics and Traumatology GuangzhouGuangdong ProvinceChina

Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord *** and astrocytes play key roles in the spinal cord injury micro-environment and share a close ***,the mechanisms involved remain *** this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming *** expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord *** vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between *** further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling ***,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling *** vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function ***,Gas6 may play a role in the treatment of spinal cord *** can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.

关键词： astrocytes Axl cell polarization Gas6 Hippo signal inflammatory micro-environment intercellular interaction microglia single-cell sequencing spinal cord injury