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Atomic-scale mechanism of effect of co-separation of elements at interface of ferrite and austenite on Cr-depleted zone of duplex stainless steel

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Journal of Iron and Steel Research International 2024年第3期31卷 710-718页

作者： Yan-hui Hou ze-kun Xu Shi-long zhou Guang-qiang Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Three-dimensional atom-probe tomography and first-principles calculation combined with density functional theory were used to study the effect of the co-segregation of different elements formed during the solidification process of S32205 duplex stainless steel on the Cr-depleted zone at the interface between ferrite and *** was found that the co-segregation of different elements formed during the solidification process of duplex stainless steel can also form Cr-depleted zone at the interface between ferrite and ***,Mo,Si,B,C and P atoms promote co-segregation with Cr atoms,which promotes the formation of Cr-depleted zone at the interface between ferrite and austenite in duplex stainless *** and Si strongly promote the segregation of Cr at the interface between ferrite and austenite,thereby promoting the formation of Cr-depleted zone.B,C and P elements also promote the segregation of Cr element at the interface between ferrite and austenite and the formation of Cr-depleted zone,but their effect is weaker than that of Mo and Si *** conclusions provide a new theoretical basis for improving the intergranular corrosion performance of duplex stainless steel.

关键词： Duplex stainless steel Cr-depleted zone Intergranular corrosion Co-segregation First-principles calculation

Partitioning of nitrogen atoms and its effect on retained austenite content in an ultra-low-carbon Cr-Mn-N stainless steel

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Journal of Iron and Steel Research International 2021年第8期28卷 1030-1036页

作者： Zhe Zhu Wan-tang Fu Rong-bin Li Qi-wei Chen ze-an zhou Zhen-hua Wang Jia-qing Liu Shu-hua Sun State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004HebeiChina Shanghai Engineering Research Center of Hot Manufacturing Shanghai Dianji UniversityShanghai 201306China School of Science Yanshan UniversityQinhuangdao 066004HebeiChina

The partitioning of nitrogen atoms and its effect on the retained austenite content(RAC)during quenching and partitioning(Q&P)process were investigated by dilatometry,X-ray diffraction,and field emission transmission electron microscopy with energy-dispersive spectrometer mapping in a 00Cr13Mn8N *** partitioning by diffusion of N atoms from martensite to austenite occurred at 400℃after quenching.N atoms are enriched in austenite after partitioning,and the stability of these N-rich austenite is improved and retained at room temperature during subsequent *** different quenching temperatures(QTs)result in different phase fractions after *** the increase in QT,RAC first increases and then decreases,and the maximum RAC is 28.5 vol.%after quenching at 80℃.A mathematical model was developed to rapidly and accurately characterize the phase fraction in Q&P process based on the relative length change of the samples partitioned after quenching at different QTs.

关键词： Nitrogen partitioning Quenching and partitioning Retained austenite Energy-dispersive spectrometer mapping Dilatometry Ultra-low-carbon stainless steel

Sperm origins and concentration do not impact the clinical outcomes in intracytoplasmic sperm injection cycles

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Asian Journal of Andrology 2018年第5期20卷 454-458页

作者： Cen Yang ze-Hong zhou Dan-Ni Zheng Xiao-Fei XU Jin Huang Ying Lian Jie Qiao Center for Reproductive Medicine Department of Obstetrics and Gynecology Peking University Third Hospital Beijing 100191 China Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproduction Technology Beijing 100191 China Key Laboratory of Assisted Reproduction Ministry Of Education Beijing 100191 China

In the present study, we evaluated the impact of sperm origins and concentration on the clinical outcomes of intracytoplasmic sperm injection （ICSI） cycles. A total of 1201 IC51 cycles were retrospectively analyzed for male azoospermia or oligozoospermia between January 2015 and December 2015 in the Peking University Third Hospital. Patients were divided into three groups （Group 1 vs Group 2/3; surgically extracted sperm vs ejaculated sperms）： Group 1 included 343 ICSI cycles and Group 2 analyzed 388 cycles on semen with sperm concentration 〈5 × 10^6 m1-1 （severe oligozoospermia group）. Group 3 included 470 cycles with sperm concentration between 5×10^6 m1-1 and 15 × 10^6 m1-1 （mild oligozoospermia group）. Fertilization rates, clinical pregnancy rates, and live birth rates were analyzed and compared among groups of different semen origins and concentrations on the oocyte retrieval day. Group 2 showed a lower fertilization rate than Group 3 （62.9%± 21.6% vs 66.8% ± 22.1%, P 〈 0.05）. There were no statistically significant differences in clinical pregnancy rate per transfer （51.3%, 46.7%, and 50.0%, respectively）, live birth rate per transfer （44.4%, 40.9%, and 41.4%, respectively）, accumulative live birth rate （58.3%, 51.0%, and 52.1%, respectively）, twin birth rate （18.4%, 10.6%, and 12.6%, respectively）, and birth defects rate （0, 0.3%, and 0.2%, respectively） among three groups. The results of this study indicated that sperm origins and concentration do not imDact the clinical outcomes in ICSI cycles.

关键词： azoospermia clinical outcomes intracytoplasmic sperm injection oligozoospermia sperm concentration

Enhancer activity of Hefitron in sericin-1 gene promoter from Bombyx mori

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Insect Science 2016年第3期23卷 396-405页

作者： Ke Huang Chun-Feng Li Jie Wu Jun-Hong Wei Yong Zou Min-Jin Han ze-Yang zhou State Key Laboratory of Silkworm Genome Biology Southwest University Chongqing College of Forestry & Life Science ChongqingUniversity of Arts & Sciences Yongchuan Laboratory of Animal Biology Chongqing Normal University Chongqing China

Sericin is a kind of water-soluble protein expressed specifically in the middle silk gland ofBombyx mori. When the sericin-1 gene promoter was cloned and a transgenic vector was constructed to express a foreign protein, a specific Helitron, Bmhel-8, was identified in the sericin-1 gene promoter sequence in some genotypes of Bombyx mori and Bombyx mandarina. Given that the Bmhel-8 Helitron transposon was present only in some genotypes, it could be the source of allelic variation in the sericin-I promoter. The length of the sericin-1 promoter sequence is approximately 1063 or 643 bp. The larger size of the sequence or allele is ascribed to the presence of Bmhel-8. Silkworm genotypes can be homozygous for either the shorter or larger promoter sequence or heterozygous, containing both alleles. Bmhel-8 in the sericin-1 promoter exhibits enhancer activity, as demonstrated by a dual-luciferase reporter system in BraE cell lines. Furthermore, Bmhel-8 displays enhancer activity in a sericin-1 promoter-driven gene expression system but does not regulate the tissue-specific expression of sericin-1.

关键词： Bmhel-8 enhancer promoter regulation sericin-I

BSTFNet:An Encrypted Malicious Traffic Classification Method Integrating Global Semantic and Spatiotemporal Features

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Computers, Materials & Continua 2024年第3期78卷 3929-3951页

作者： Hong Huang Xingxing Zhang Ye Lu ze Li Shaohua zhou School of Computer Science and Engineering Sichuan University of Science&EngineeringYibin644002China School of Mathematics and Statistics Sichuan University of Science&EngineeringYibin644002China

While encryption technology safeguards the security of network communications,malicious traffic also uses encryption protocols to obscure its malicious *** address the issues of traditional machine learning methods relying on expert experience and the insufficient representation capabilities of existing deep learning methods for encrypted malicious traffic,we propose an encrypted malicious traffic classification method that integrates global semantic features with local spatiotemporal features,called BERT-based Spatio-Temporal Features Network(BSTFNet).At the packet-level granularity,the model captures the global semantic features of packets through the attention mechanism of the Bidirectional Encoder Representations from Transformers(BERT)*** the byte-level granularity,we initially employ the Bidirectional Gated Recurrent Unit(BiGRU)model to extract temporal features from bytes,followed by the utilization of the Text Convolutional Neural Network(TextCNN)model with multi-sized convolution kernels to extract local multi-receptive field spatial *** fusion of features from both granularities serves as the ultimate multidimensional representation of malicious *** approach achieves accuracy and F1-score of 99.39%and 99.40%,respectively,on the publicly available USTC-TFC2016 dataset,and effectively reduces sample confusion within the Neris and Virut *** experimental results demonstrate that our method has outstanding representation and classification capabilities for encrypted malicious traffic.

关键词： Encrypted malicious traffic classification bidirectional encoder representations from transformers text convolutional neural network bidirectional gated recurrent unit

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重叠社区发现算法评价指标综述

计算机技术与发展 2024年第5期34卷 1-9页

作者：韩红旗徐紫燕李琳娜周则旭中国科学技术信息研究所北京100038 富媒体数字出版内容组织与知识服务重点实验室(国家新闻出版署) 北京100038

重叠社区发现算法对于理解复杂系统、发现复杂网络中隐藏的规律等具有很强的应用价值,而评价指标是算法发现高质量重叠社区的一个关键要素,算法的进步常常依赖于评价指标的进步。现有研究对非重叠社区发现算法的评价指标有较多的总结,... 详细信息

重叠社区发现算法对于理解复杂系统、发现复杂网络中隐藏的规律等具有很强的应用价值,而评价指标是算法发现高质量重叠社区的一个关键要素,算法的进步常常依赖于评价指标的进步。现有研究对非重叠社区发现算法的评价指标有较多的总结,而没有对重叠社区发现算法的评价指标进行总结。对重叠社区发现算法的评价指标进行了系统的总结和回顾,将指标分为事先知道社区结构、事先不知道社区结构和其它三大类。事先知道社区结构的评价指标包括基于混淆矩阵、基于ARI、基于NMI三个子类评价指标,事先不知道社区结构的评价指标包括基于模块度、基于密度、基于元数据三个子类评价指标,其它类主要介绍算法可扩展性评价指标。深入理解各种评价指标对于开发和优化重叠社区发现算法、在实际应用中发现高质量社区具有重要价值。

关键词：重叠社区评价指标社区发现社区结构复杂网络

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贵州化处矿区煤炭地下气化物理模拟试验

中国煤炭地质 2024年第8期36卷 17-25页

作者：周泽汪凌霞金黎黎易同生孔维敏梁杰贵州省煤田地质局贵州贵阳550081 贵州优驰能源科技有限责任公司贵州贵阳550014 贵州省煤炭流态化开采重点试验室贵州贵阳550014 中国矿业大学(北京)化学与环境工程学院北京100083

为了深入探究贵州六枝化处矿区贫煤气化工艺参数,稳步推进贵州煤炭地下气化工程示范,开展了系列地下气化物理模拟试验和理论分析。通过构建综合模型系统,模拟了不同氧气浓度、气化炉结构和煤层湿度等条件下的气化过程,系统地探究了贫煤... 详细信息

为了深入探究贵州六枝化处矿区贫煤气化工艺参数,稳步推进贵州煤炭地下气化工程示范,开展了系列地下气化物理模拟试验和理论分析。通过构建综合模型系统,模拟了不同氧气浓度、气化炉结构和煤层湿度等条件下的气化过程,系统地探究了贫煤地下气化的特性、气化效率和气化工艺参数等。试验结果表明,气化炉结构差异对合成气组分有显著影响,同时,气化通道的支护方式、气化剂浓度、煤层含水量也会影响合成气组分。在适当的氧气浓度下,贵州六枝化处地区的贫煤能够稳定气化产出合成气,70%以下富氧环境下,随着氧气浓度的增加,煤气有效组分逐渐提高,煤气热值也相应增加;超过70%富氧时,有效组分中CO含量开始下降;温度场方面,气化过程的推进会直接影响温度场推移方向,且在煤层中会存在高低温区交叉分布的特征,主要是由于煤层中煤块之间存在裂隙,形成绕流燃烧而引起的。后期实际生产中,要控制气化剂氧气浓度,提高气化效率;钻井底部加强支护,采取热胀冷缩保护;增加辅助措施维持气化炉内温度场稳定性;为了提高H_(2)、CO组分浓度,需注入雾化水,增加还原性。通过深入探究不同工艺参数条件下贵州化处矿区贫煤地下气化特性,为下一步实际生产中气化工艺参数优化、气化效率提高和煤气质量提升提供了科学数据支撑。

关键词：煤炭地下气化物理模拟气化工艺参数贫煤

UVB suppresses PTEN expression by upregulating miR-141 in HaCaT cells

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The Journal of Biomedical Research 2011年第2期25卷 135-140页

作者： Wei Li Wu Di Lijuan Hua Bingrong zhou ze Guo Dan Luo Department of Dermatology the First Affiliated Hospital of Nanjing Medical University Nanjing Jiansu 210029 China

MicroRNAs （miRNAs） are 21 to 24 nucleotide, non-coding RNA molecules that post-transcriptionally regulate the expression of target genes. Ultraviolet B （UVB） radiation has been shown to inhibit phosphatase and tensin homolog deleted on chromosome 10 （PTEN） expression in HaCaT cells through an unknown mechanism. In this study, we investigated whether miR-141 can regulate UVB exposure-mediated inhibition of PTEN expression. Real-time RT-PCR, annexin V/fluorescein isothiocyanate staining, Western blotting and anti-miRNA oligonucleotide transfection were employed in this study. We found that upregulation of miR-141 expression after UVB irradiation was inversely correlated with PTEN expression levels in HaCaT cells. Furthermore, miR-141 expression increased apoptosis, while anti-miR-141 partly restored PTEN expression and reversed the pro-apoptosis effect of UVB. UVB suppresses the expression of PTEN by upregulating miR-141 in HaCaT cells. Therefore, miR-141 is a potential gene therapy target for UVB-induced photodamage.

关键词： MicroRNA-141 PTEN UVB apoptosis HaCaT cells

Effect of dynamic loading orientation on fracture properties of surrounding rocks in twin tunnels

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 393-409页

作者： ze Deng Zheming Zhu Lei zhou Leijun Ma Jianwei Huang Yao Zhang Key Laboratory of Deep Earth and Engineering(Ministry of Education) College of Architecture and EnvironmentSichuan UniversityChengdu610065China Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan Province College of Architecture and EnvironmentSichuan UniversityChengdu610065China Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu610065China

For expedited transportation,vehicular tunnels are often designed as two adjacent tunnels,which frequently experience dynamic stress waves from various orientations during blasting *** analyze the impact of dynamic loading orientation on the stability of the twin-tunnel,a split Hopkinson pressure bar(SHPB)apparatus was used to conduct a dynamic test on the twin-tunnel *** two tunnels were rotated around the specimen’s center to consider the effect of dynamic loading ***-DYNA software was used for numerical simulation to reveal the failure properties and stress wave propagation law of the twin-tunnel *** findings indicate that,for a twin-tunnel exposed to a dynamic load from different orientations,the crack initiation position appears most often at the tunnel corner,tunnel spandrel,and tunnel *** the impact direction is created by a certain angle(30°,45°,60°,120°,135°,and 150°),the fractures are produced in the middle of the line between the left tunnel corner and the right tunnel *** the impact loading angle(a)is 90°,the tunnel sustains minimal damage,and only tensile fractures form in the surrounding *** orientation of the impact load could change the stress distribution in the twin-tunnel,and major fractures are more likely to form in areas where the tensile stress is concentrated.

关键词： Twin-tunnel Dynamic load Split Hopkinson pressure bar(SHPB) Fracture mode Stress distribution Displacement field distribution