Experimental investigation on tensile strength of butt welded joint post high temperatures

In order to investigate the laws of variation on tensile strength of butt welded joint post high temperatures, the wide plate tension tests for butt welded joint were conducted after cooling down from different high temperatures. The tests indicate that specimens appear ductile fracture at the steel plate during the tension tests after cooling down. The maximum temperatures undergone and the cooling pattern are major factors influencing tensile strength of butt welded joint post high temperatures. The tensile strength mostly reduces by 8% within 900℃. Based on the experimental results, the paper proposes the calculation formulas of tensile strength of butt welded joint post high temperatures. The conclusions of the paper supply references for evaluation damage and reinforcement of steel structure post fire.

Experimental study on the shear strength of side fillet weld of Q235B steel post high temperatures

In order to learn the variation laws of shear strength of side fillet weld post high temperatures, the tension tests were conducted after the double-strapped side fillet welded joints which were cooled down from different high temperatures with different cooling patterns. The tests indicate that specimens appear brittle fracture at the side fillet weld during the tension tests after cooling down. The fracture su（face is located in the welding throat. The maximum temperatures undergone and the cooling pattern are major factors influencing shear strength of side fillet welded joint post high temperatures. The shear strength reduces by 24% at most within 900 ~C. Based on the experimental results, the calculation formulas of shear strength of side fillet weld post high temperatures were proposed. Conclusions supply references for evaluation damage and reinforcement of steel structure post fire.

Predictors of post-treatment stenosis in cervical esophageal cancer undergoing high-dose radiotherapy

AIM To evaluate toxicity and treatment outcome of highdose radiotherapy(RT) for cervical esophageal cancer(CEC).METHODS We reviewed a total of 62 consecutive patients who received definitive RT for stage Ⅰ to Ⅲ cervical esophageal cancer between 2001 and 2015. Patients who received < 45 Gy, treated for lesions below sternal notch, treated with palliative aim, treated with subsequent surgical resection, or diagnosed with synchronous hypopharyngeal cancer were excluded. Treatment failures were divided into local(occurring within the RT field), outfield-esophageal, and regional [occurring in regional lymph node(s)] failures. Factors predictive of esophageal stenosis requiring endoscopic dilation were analyzed.RESULTS Grade 1, 2, and 3 esophagitis occurred in 19(30.6%), 39(62.9%), and 4 patients(6.5%), respectively, without grade ≥ 4 toxicities. Sixteen patients(25.8%) developed post-RT stenosis, of which 7 cases(43.8%) were malignant. Four patients(6.5%) developed tracheoesophageal fistula(TEF), of which 3(75%) cases were malignant. Factors significantly correlated with post-RT stenosis were stage T3/4(P = 0.001), complete circumference involvement(P < 0.0001), stenosis at diagnosis(P = 0.024), and endoscopic complete response(P = 0.017) in univariate analysis, while complete circumference involvement was significant in multivariate analysis(P = 0.003). A higher dose(≥ 60 Gy) was not associated with occurrence of postRT stenosis or TEF. With a median follow-up of 24.3(range, 3.4-152) mo, the 2 y local control, outfield esophageal control, progression-free survival, and overall survival(OS) rates were 78.9%, 90.2%, 49.6%, and 57.3%, respectively. Factors significantly correlated with OS were complete circumference involvement(P = 0.023), stenosis at diagnosis(P < 0.0001), and occurrence of post-RT stenosis or TEF(P < 0.001) in univariate analysis, while stenosis at diagnosis(P = 0.004) and occurrence of post-RT stenosis or TEF(P = 0.023) were significant in multivariate analysis. CONCLUSION Chemoradiation for CEC was well tolerated, and a higher dose was not associated with stenosis. Patients with complete circumferential involvement require close follow-up.

Extensional Tectonic Framework of Post High and Ultrahigh Pressure Metamorphism in Dabieshan,China

The most prominent feature of the extensional tectonic framework of post high pressure (HP) and ultrahigh pressure (UHP) metamorphism in Dabieshan is the development of the multi layered extension detachment zones surrounding the core of the Luotian dome, and the separation of the UHP, HP and epidote blueschist units by the detachment zones, which form the vertically stacking sheet like slices of the HP and UHP metamorphic rocks. From the core outwards, exist the HP and UHP rock barren Dabie complex, UHP unit, HP unit and epidote blueschist unit. The extension tectonics of post HP and UHP metamorphic event constrain the distribution and present configuration of the HP and UHP metamorphic rocks, and the extensional tectonic framework bears some similarities to the Cordillera metamorphic core complex. It is suggested that partial melting happened in the Dabie gneiss complex (DGC) and UHP unit contemporaneously with the extrusion of UHP metamorphic rocks into the lower-middle crust. The formation and emplacement of the migmatite and granites are the response to the change in thermal state, facilitating the transfer from the compressive regime to extensional regime in the crust. The large scale crustal extension and uplift and the accompanying anatexis in Dabieshan are probably related to the delamination and magmatic underplating in the mantle and the lower crust.

Colonoscopy surveillance for high risk polyps does not always prevent colorectal cancer

AIM To determine the frequency and risk factors for colorectal cancer(CRC) development among individuals with resected advanced adenoma(AA)/traditional serrated adenoma(TSA)/advanced sessile serrated adenoma(ASSA). METHODS Data was collected from medical records of 14663 subjects found to have AA, TSA, or ASSA at screening or surveillance colonoscopy. Patients with inflammatory bowel disease or known genetic predisposition for CRC were excluded from the study. Factors associated with CRC developing after endoscopic management of high risk polyps were calculated in 4610 such patients who had at least one surveillance colonoscopy within 10 years following the original polypectomy of the incident advanced polyp. RESULTS84/4610(1.8%) patients developed CRC at the polypectomy site within a median of 4.2 years(mean 4.89 years), and 1.2%(54/4610) developed CRC in a region distinct from the AA/TSA/ASSA resection site within a median of 5.1 years(mean 6.67 years). Approximately, 30%(25/84) of patients who developed CRC at the AA/TSA/ASSA site and 27.8%(15/54) of patients who developed CRC at another site had colonoscopy at recommended surveillance intervals. Increasing age; polyp size; male sex; right-sided location; high degree of dysplasia; higher number of polyps resected; and piecemeal removal were associated with an increased risk for CRC developmentat the same site as the index polyp. Increasing age; right-sided location; higher number of polyps resected and sessile endoscopic appearance of the index AA/TSA/ASSA were significantly associated with an increased risk for CRC development at a different site. CONCLUSION Recognition that CRC may develop following AA/TSA/ASSA removal is one step toward improving our practice efficiency and preventing a portion of CRC related morbidity and mortality.

Automatic Extraction of Urban Road Centerlines from High-Resolution Satellite Imagery Using Automatic Thresholding and Morphological Operation Method

The commercial high-resolution imaging satellite with 1 m spatial resolution IKONOS is an important data source of information for urban planning and geographical information system (GIS) applications. In this paper, a morphological method is proposed. The proposed method combines the automatic thresholding and morphological operation techniques to extract the road centerline of the urban environment. This method intends to solve urban road centerline problems, vehicle, vegetation, building etc. Based on this morphological method, an object extractor is designed to extract road networks from highly remote sensing images. Some filters are applied in this experiment such as line reconstruction and region filling techniques to connect the disconnected road segments and remove the small redundant. Finally, the thinning algorithm is used to extract the road centerline. Experiments have been conducted on a high-resolution IKONOS and QuickBird images showing the efficiency of the proposed method.

后职业发展:构建高质量老年教育体系的逻辑路向

基于积极老龄化理念,响应党的二十大报告提出的“建设高质量教育体系”号召,老年人“后职业发展”应该成为构建高质量老年教育体系的路向指引,进而发挥延伸老年人职业生涯、释放老年人力资本、增进社会民生福祉的多重功能。“后职业发展”型高质量老年教育体系的核心要素包括重点目标、主要内涵、基本原则及运行机制。构建“后职业发展”型高质量老年教育体系,需要树立“增权赋能”老年教育理念,探索“职老贯通”老年教育融合发展模式,丰富老年人“求职创业”类特色课程资源,开展促进老年人内倾性成长的教育质量评价。

Permian High Ba-Sr Granitoids:Geochemistry,Age and Tectonic Implications of Erlangshan Pluton,Urad Zhongqi,Inner Mongolia

Erlangshan Pluton from Urad Zhongqi, central Inner Mongolia, is located in the middle segment of the northern margin of the North China Plate. The rocks consist mainly of diorites with gneissic structure. Petrochemical characteristics reveal that the diorites belong to metaluminous, high- potassium calc-alkaline series, with chemical signatures of I-type granites. They are characterized by low SiOz contents (56.63%-58.53%) and A/CNK (0.90-0.96), high Al2O3 contents (17.30%-17.96%) and Na20/K20 ratios (1.20-1.70), enrichment in large ion lithophile elements (LILE, e.g., Ba=556-915 ppm, Sr=463-595 ppm), and relative depletion in high field strength elements (HFSE, e.g., Nb, Ta, Ti) in primitive mantle-normalized spidergram, and right-declined rare earth element patterns with slightly negative Eu anomalies (8Eu=0.72-0.90). They have Sr/Y ratios (20-25) evidently less than Kebu Pluton (49-75) to its east. Sensitive high resolution ion micro-probe U-Pb zircon dating of the diorites has yielded an intrusive age of 270±8 Ma. This leads us to conclude that Erlangshan diorites were formed by mixing between the middle or lower crustal-derived magma and minor mantle-derived mafic magma, followed by fractional crystallization, which was trigged by crustal extension and fault activity in post-collisional setting.

起重船用高强钢大厚板焊接残余应力的试验研究

以某型起重船结构为研究对象,采用焊接后热作为焊接残余应力消除措施,研究结构的残余应力情况及消除措施的有效性。首先采用焊态和经过焊接后热的两组试板进行焊接残余应力检测并对比,结果表明焊态的试板焊接纵向残余应力最高达552.5 MPa,接近材料的屈服强度;经后热的试板纵向残余应力最大为385.3MPa,与焊态相比降低了167.2 MPa,下降约30%;同时获取了残余应力分布情况。进一步对起重船导向基座结构的焊缝进行后热并进行应力检测,其纵向焊接残余应力最大值为310.8 MPa,远低于母材屈服强度。本文研究表明:起重船高强钢大厚板在焊态时焊接残余应力较大,需采取措施消除残余应力;采用焊接后热可以大幅降低高强钢大厚板的焊接残余应力水平,焊接后热具有较好的经济性和操作便捷性,在起重船建造过程中建议考虑对大厚板焊缝进行后热以消除焊接残余应力消除。

基于震后复旧工程的断裂带区域轨道设计借鉴

针对兰新高铁震后轨道伤损评估及复旧工程设计无章可依且无经验可借鉴的情况,基于震后复旧工程设计,对断裂带区域轨道结构选型与设计有关经验进行分析。除大梁隧道F5断裂外,钢轨扭曲变形及扣件破坏主要发生在硫磺沟大桥上,是由地震荷载下桥梁支座螺栓剪断后梁体移位落梁,相邻梁体变形差异大引起。道床板存在局部1~2 m范围碎裂,主要与地震横波、纵波传递过程中的叠加有关。个别段落出现轨道不平顺超限的情况,主要是受线下基础类型和地质条件差异等因素影响。震后复旧工程应首先基于基准点的测设与平差开展区域性线形重构与拟合;断裂带区域轨道设防长度根据有砟轨道养护维修最小段落长度确定,不能满足震后轨道结构的调整需求,建议结合预估错位量及线路拟合范围、轨道调整能力综合确定;近断裂带区域无砟轨道建议采用无挡肩轨枕,在地震情况下使扣件弹条或者锚固螺栓发生破坏,而轨枕保持完整,以降低震后复旧工程难度及代价;为确保特殊条件下的整治效果,建议采取特种整治措施。

香型优质虾后稻新品种福香9号的选育与应用

福香9号是以华润2号和鄂恢71为亲本,通过系谱法和分子标记辅助选择相结合选育的优质常规香型水稻(Oryza sativa L.)新品种,于2023年通过湖北省农作物品种审定委员会审定。该品种生育期短、米质优、香味浓郁、食味口感好,尤其适合作虾后稻。栽培上应适时播种,适当增加播种量,同时控氮增钾,提高抗倒性。

Effects of Microstructural Modification Using Friction Stir Processing on Fatigue Strength of Butt-Welded Joints for High-Strength Steels

Friction stir processing (FSP) is an effective surface-microstructure modification technique using a rotational tool to refine and homogenize microstructure of metallic materials. In this study, FSP was conducted on the surface of the heat-affected zone (HAZ), which is a region exhibiting degraded mechanical properties and shown to have microstructural changes, of butt-welded joints for two high-strength steels with tensile strength grades of 490 MPa and 780 MPa (hereafter HT490 and HT780, respectively). Inhomogeneous mixing of materials derived from weld metals and base metals (BMs) in a stir zone (SZ) produced inhomogeneous distribution of elements and microstructure depending on the set of the advancing side and retreating side in the SZs. The welded joints with FSP for HT490 exhibited higher hardness than that of the BM through whole of the SZ surface (fine polygonal ferrite grains and bainite structure with laths at the Mn-rich and Mn-poor regions, respectively). On the other hand, those for HT780 exhibited the minimum hardness value similar to that of the BM at the SZ surface (a few polygonal ferrite grains in the matrix of martensite laths). Fatigue strength increased by about 35 MPa and 15 MPa in stress amplitude at 107 cycles as fatigue limit due to FSP. Fatigue failure occurred at the BM and the SZ, respectively, in the welded joints modified by FSP for HT490 and HT780, in comparison with the HAZs in the as-welded joints for both grade steels. The difference in fatigue strength increase due to FSP and failure location between the welded joints for HT490 and HT780 can be attributed to the topmost SZ microstructures and their distribution.

审视与定位:后冬奥时期我国滑雪产业高质量发展中的政府角色

政府角色的合理定位对滑雪产业高质量发展具有重要的推动与保障作用。通过文献资料、实地调研和访谈等研究方法对后冬奥时期滑雪产业高质量发展的内在表征及政府失灵的外在表现进行深入分析,审视滑雪产业发展中政府角色定位的实践特征,进而明确政府的应然角色。研究发现:后冬奥时期滑雪产业市场主体、市场环境和现代化治理之间有效协同才能实现滑雪产业的高质量发展,然而政府治理滑雪产业高质量发展过程中却存在角色缺位、错位、越位的风险。结合滑雪产业具有资源依赖性特征明显,产业容错率低;兼具商品属性和公益属性,具有正负外部性;属于重资产投资项目,受投融资政策影响;滑雪市场主体多元化,市场机制尚不健全等实践特征。后冬奥时期,政府应该扮演规划者、监督者、保障者和协调者等应然角色,不断优化政府行为,进而实现滑雪产业的高质量发展。

Sleep Quality for Patients Receiving Noninvasive Positive Pressure Ventilation and Nasal High-Flow Oxygen Therapy in an ICU: Two Case Studies

Aim: The purpose of this case study was to examine the sleep quality of patients receiving noninvasive positive pressure ventilation (NPPV) or nasal high-flow oxygen therapy (NHF) in an intensive care unit and to investigate what types of nursing support are offered to such patients. Methods: We examined one patient each for NPPV and NHF. Polysomnography (PSG), review of the patient charts, and semi-structured interviews were used to collect the data for analysis. Results: Patients treated with NPPV or NHF demonstrated a noticeable reduction in deep sleep, with most of their sleep being shallow. Their sleep patterns varied greatly from those of healthy individuals. These results suggest that, in addition to experiencing extremely fragmented sleep, sleep in these patients was more likely to be interrupted by nursing interventions, such as during auscultation of breath sounds. Furthermore, it was revealed that “anxiety or discomfort that accompanies the mask or air pressure” in patients treated with NPPV and “discomfort that accompanies the nasal cannula or NHF circuit” in patients treated with NHF may be primary causes of disrupted sleep. Our results suggest a need for nursing care aimed at improving sleep quality in patients treated with NPPV or NHF.

基于岗位需求导向的电子信息专业“岗课赛证”融合育人模式

目前,部分高职院校的人才培养模式满足不了社会和企业对高技能人才的需求。为了解决这一问题,针对电子信息专业的企业用人需求,深入探索研究专业领域内的“岗课赛证”融合育人机制。通过企业岗位调研、校企开发课程标准和模块、引导并组织学生参加相关专业赛项以及以证抵学分等方式,激发了学生学习的主动性,培养了学生综合素养,使得学生的岗位实践能力得到用人单位认可,实现了企业用人需求、高职院校人才培养、学生自我能力展现之间的高度融合。因此,“岗课赛证”融合育人模式研究具有重要的现实意义。

Post-noon ionospheric absorption observed by the imaging riometers at polar cusp/cap conjugate stations

An example of post-noon ionospheric absorption observed by the imaging riometers at Ny-Alesund / Danmarkshavn in the arctic region and Zhongshan Station in Antarctic is presented. The post-noon absorption observed simultaneously between the hemispherical stations was a spike-type with weak intensity (<1 dB) during the high solar wind dynamic pressure. The absorption spikes might be caused by precipitation of highrenergy electrons (30 - 300 keV) in the closed dayside magnetosphere. It should be noted that the precipitation region of the absorption spike associated with the steep pressure increase (~ 13 nPa) was localized and shifted equatorward.

高职院校“岗课赛证”融合育人模式的理论与实践研究

“岗课赛证”融合育人模式是继产教融合、全国职业技能大赛、1+X证书制度等项目而提出的高等职业教育建设项目。该模式主要从标准、内容、过程、评价四个维度的相互融合,促进高职院校教育教学改革,提高高等职业教育人才培养的质量。现阶段,“岗课赛证”融合育人模式存在功利化、形式化、结果化三个方面的现实困境,缺少有效的实施途径。因此,高职院校专业建设应坚持岗位需求导向,“以岗定课”建设课程体系,“以赛促教”推动课程教学改革,“以证定标”构建多维评价体系,以助力实现高素质技术人才培养的跃迁。

花后高温胁迫对小麦籽粒萌发及相关酶活性影响

【目的】研究小麦花后高温处理对其籽粒发芽和生长的影响,分析小麦响应花后高温逆境的生理机制。【方法】以新疆主栽小麦品种新春11号为材料,取小麦成熟后的籽粒,待小麦开花后5~8 d时进行高温处理,研究其萌发特性以及相关酶活性。【结果】小麦籽粒在经过高温处理后,籽粒发芽率和发芽势与对照相比较显著降低(分别降低5.10%和3.22%),电导率指标极显著高于对照(高出22.78%)。经过花后高温处理,小麦籽粒萌发并且长成嫩芽的芽长以及芽鲜重,与对照相比较显著降低17.98%和12.84%;在小麦籽粒萌发中,发芽指数和活力指数均显著下降。种子活力(TTC还原强度)的变化虽然差异不显著,但降低程度达26.02%。【结论】小麦开花后遭受高温胁迫,导致籽粒中酶活性下降,最终造成种子活力降低,并且减缓了小麦幼苗时期的长势,小麦的产量亦受到影响。

积极心理干预对中学生创伤后成长的影响

对经历过重大校园危机事件的中学生开展积极心理干预团体辅导干预的实验研究,结果表明,实施积极心理干预能够提高中学生创伤后成长水平,传统心理干预中蕴含着积极趋向与积极价值,可以在一定程度上提高中学生创伤后成长水平。为提高中学生的心理健康水平,学校要重视学生心理健康教育,坚持积极心理干预与传统心理干预相结合,并推广以班级为单位的积极心理干预团体辅导活动。

高压SF_(6)断路器电流零区测量研究综述

电流零区测量对标定评价断路器开断性能、改进断路器结构设计至关重要,设计一套高精度、便携、可靠、安全的零区测量系统一直是行业的追求,国内外研究者在测量方法和测量装置研制方面做了很多创新性工作。从高压断路器灭弧原理出发,梳理提出了零区测量的难点和关键点,综述了国内外研究者提出的测量方案及效果。综合考虑多维度产业需求,研制了一套便携性和动态特性好的零区测量系统,并在实际断路器产品试验中进行了验证。结果表明:该系统抗干扰性和重复性好,能够满足产品研发需求。结合零区测量系统研究及使用经验,提出了零区测量系统的未来展望,为后续交直流开关的研发提供参考。