南海高温高压钻完井关键技术及工程实践

南海是全球三大海上高温高压区域之一,地质构造复杂,已钻井井底温度249℃、压力梯度2.4 MPa/100 m、CO_2含量50%,该区域油气资源勘探开发长期受异常压力预测误差大、井筒泄漏及环空带压严重、测试安全风险高、成本巨高等钻完井技术瓶颈制约。全面总结了近20年南海高温高压钻完井在异常压力精确预测及控制、多级屏障井筒完整性、多因素多节点测试、优质高效作业等4个方面研究形成的关键技术及工程实践,展望了南海高温高压钻完井技术未来发展方向。以期为进一步加快南海及其他地区类似高温高压区块油气资源高效可持续勘探开发提供指导。

混凝土质量缺陷修补工程实践

本文依托某核电工程空压机房框架柱混凝土麻面、蜂窝、孔洞质量缺陷的产生原因分析、修补处理方案以及修补结果进行阐述,并结合工程实际,提出了合理可行的混凝土质量缺陷修补方案,对类似工程混凝土缺陷的修复起到了指导作用。

工程认证背景下实践课程成绩评定方法与应用

随着非标准化考试等教学改革的推进,课程成绩评定成为高校实践类课程的重要考核方式。然而,由于缺乏客观定量的评价方法,主观性考核方式在认定考生成绩时存在较大不确定性。如何有效降低主观评判的随意性和不确定性成为课程成绩核定亟须解决的问题。研究提出基于师生协作的综合成绩评估方法,采用动态权重法综合学生打分和教师打分,形成更加合理的综合成绩分布,并以本科必修课程“环境规划与管理”期末成绩评定为例开展案例研究。结果表明,合理应用学生打分能够改善学生成绩分布,但要注意规避学生打分可能存在的均一化倾向和简单等权评分带来的成绩偏态分布问题。研究成果以期为大学实训类课程成绩评定提供一种新的方法。

高职院校“建设工程法规”课程思政的探索与实践——以工程造价专业为例

为落实加强党对职业教育工作的全面领导,实现职业技能和职业精神培养高度融合的要求,“建设工程法规”课程的教学内容决定了教师必须承担起学生法治精神培养等思想政治教育的任务,积极探索课程思政开展的具体方式方法,落实立德树人根本任务。针对高职院校工程造价专业,对“建设工程法规”的思政入课实践方法和教学设计展开探索,基于互动教学,列举主要章节思政元素如何与知识和技能相结合,实现职业能力和职业素质双融合培养。

行业特色高校外语“3+”培养模式创新与实践——以西安某高校高起点班为例

文章在高校人才培养多元化的趋势和大学英语改革的新背景下,以西安某行业特色型高校为例,论述了高起点本科生英语培养方案、目标及课程设置。并通过社会调查和课堂教学实践构建了一个针对高水平本科生的外语培养及教学模式,试图解决目前理工科院校大学英语课程设置不合理及教学模式单一的现象,为当前的高校的外语教育和外语改革提供一定的借鉴和参考作用。

Shear modulus and damping ratio of sand-granulated rubber mixtures

Recycled waste tires when mixed with soil can play an important role as lightweight materials in retaining walls and embankments, machine foundations and railroad track beds in seismic zones. Having high damping characteristic, rubbers can be used as either soil alternative or mixed with soil to reduce vibration when seismic loads are of great concern. Therefore, the objective of this work was to evaluate the dynamic properties of such mixtures prior to practical applications. To this reason, torsional resonant column and dynamic triaxial experiments were carried out and the effect of the important parameters like rubber content and ratio of mean grain size of rubber solids versus soil solids(D50,r/D50,s) on dynamic response of mixtures in a range of low to high shearing strain amplitude from about 4×10-4% to 2.7% were investigated. Considering engineering applications, specimens were prepared almost at the maximum dry density and optimum moisture content to model a mixture layer above the ground water table and in low precipitation region. The results show that tire inclusion significantly reduces the shear modulus and increases the damping ratio of the mixtures. Also decrease in D50,r/D50,s causes the mixture to exhibit more rubber-like behavior. Finally, normalized shear modulus versus shearing strain amplitude curve was proposed for engineering practice.

The practice of mine ventilation engineering

The practice of ventilation is continually evolving with new technological advances developed in the mining industry.In recent years the advances in diesel engine technologies,ventilation modeling software,and ventilation management capacities have redefined the historical methods used to evaluate systems.The advances re-evaluate previous methods used to calculate the airflow requirements for the dilution of diesel exhaust fumes.Modeling software has become an integral part of planning and developing ventilation systems in partnership with graphical mine design software packages to generate realistic representations of the mine.Significant advances in ventilation control strategies through remote sensors and monitoring capabilities have been developed to results in cost savings.Though there has been much advancement in mine ventilation technology,the practices and basic ventilation principals enacted through the ventilation engineer cannot be placated with technological advances only.

Numerical Investigation of a New Method for Reducing Bends Erosion from Particles Impacts

The present paper intends to introduce a new method for reducingbends erosion from particles impacts: the ribbed bend erosionprotection method. Ribs are evenly fixed in the range of 20 deg-80deg on the inner-wall of inside 90 deg bend and the bend (includingribs) is made of medium carbon steel. Three-dimensional numericalworks is performed and the result shows satisfactory agreement withthe experimental measurement. Numerical simulation studies thecharacteristics of axial gas flow along the bend and secondary flowat cross section.

Optimization of construction scheme and supporting technology for HJS soft rock tunnel

For a soft rock tunnel under high stress in jointed and swell soft rock （HJS）, two construction schemes pilot-tunneling enlarging excavation and step-by-step excavation were optimized using FLAC20, and the deformation effects of the two construction schemes were verified by field tests. Based on engineer- ing geological investigation and mechanical analysis of large deformations, the complex deformation mechanisms of stress expansion and structural deformation of the soft rock tunnel were confirmed, and support countermeasures from the complex deformation mechanism converted to a single type were proposed, and the support parameters were optimized by field tests. These technologies were proved by engineering practice, which produced significant technical and economic benefits.

The principle of stability control of surrounding rock-bearing structures in high stress soft rock roadways

Through the description of the deformational features of the surrounding rockaround high stress engineering soft rock roadways,the coupling stabilization principle ofinner and outer structures in surrounding rock was put forward.The supporting principlesof high stress engineering soft rock roadway (high resistance and yielding support,timelysupport,high strength and high stiffness supports) were proposed,which were applied inengineering practices,and obtained better achievements.

Nitrosation Reaction Without Nitrogen Oxide Waste Gas Emission and Its Engineering Practice

The gas-liquid phase equilibrium is used in controlling the nitrosation reaction process. Decomposition of nitrous acid and oxidation side reaction.are suppressed in a closed reaction system. The system pressure is used as the criterion of the end of reaction, avoiding excessive feeding and reducing＇the decomposition＇of nitrous acid. The head space of the reactor is used as the gas buffer, stabilizing the feeding fluctuations and inhibiting the side reaction, decomposition of nitrous acid. Nitrogen oxide concentration is controlled at the minimum level.Thus the zero release ofnitrogen ox!de waste gas can be achieved without using any absorption process.

Experimental investigation on the energy-saving diffuser of a main fan

The main fan diffuser in a coal mine is an energy-recycling equipment with a dynamic energy loss for the main fan. Engineering practices and related researches show that the body structures of three types of diffusers are irrational. To solve the problem, an energy-saving diffuser is designed on the basis of the velocity potential theory. Under conditions of inlet velocity from 7 m/s to 32 m/s, 7 condition experiments using the energy-saving diffuser of 2.31 AER （area-enlarging ratio） and 5 condi- tion experiments using the energy-saving diffuser of 2.00 AER were conducted. Through a comparative analysis of the experi- ments, the results show that the COP （coefficient of performance） of the energy-saving diffuser of 2.31 AER is better than that of the energy-saving diffuser of 2.00 AER.

Scoping biology-inspired chemical engineering

Biology is a rich source of great ideas that can inspire us to find successful ways to solve the challenging problems in engineering practices including those in the chemical industry. Bio-inspired chemical engineering(Bio Ch E)may be recognized as a significant branch of chemical engineering. It may consist of, but not limited to, the following three aspects: 1) Chemical engineering principles and unit operations in biological systems; 2) Process engineering principles for producing existing or developing new chemical products through living ‘devices';and 3) Chemical engineering processes and equipment that are designed and constructed through mimicking(does not have to reproduce one hundred percent) the biological systems including their physical–chemical and mechanical structures to deliver uniquely beneficial performances. This may also include the bio-inspired sensors for process monitoring. In this paper, the above aspects are defined and discussed which establishes the scope of BioChE.

The design of double line five step ship lock of Three Gorges Project

The general design and layout of the double-line five-step ship-lock,the water delivery technique for high head ship-lock,the key technical problems of fully lined ship-lock and the monitoring techniques for large-scale miter gates and hoisting equipment under complicated operation conditions of Three Gorges Project (TGP) are introduced.Since the operation of ship-lock in 2003,the operation practice has proved that the design techniques are advanced,rational and reliable.The design and construction of the fully lined ship-lock promotes the development of design theory and practice of ship-lock projects,which makes the construction technology of ship-lock in the world reach a new level.

高中英语阅读新课程教学实践研究

正确的运用阅读教育这种方法,能够使学生学会英语知识,理解一些英语文章的含义,能让学生掌握阅读的能力方法和技巧,还能使学生学会用英语获取信息,分析问题,解决问题。文章针对高中英语阅读新课程教学进行了简要分析。

Vibration mechanism research of large-scale and deep-water caisson

According to the construction method of Taizhou Bridge, numerical simulation is conducted to analyze the vibration of caisson under wind and water flows to determine the main factors of the caisson vibration. Meanwhile, the localization system of caissons and anchors of Taizhou Bridge is modeled in order to summarize the vibration mechanism of caissons under deep-water and jet-flow condition, and further pertinent vibration-control measures are proposed. The obtained results are well verified in engineering practice, and consequently the safety risk of positioning the caisson is reduced.

Investigation of Correlation between the Temperature on Air-Snow and Snow-Ice Interfaces and the Atmospheric Air Temperature

Solution of the practical problems of the ice engineering requires the data about the strength of the ice cover that depends upon its temperature. In most cases, the snow lies on the ice cover and the ice temperature differs from the atmospheric air temperature. To reveal the correlation of the air temperature with temperature on interfaces air-snow and snow-ice, the known in the thermophysics solution of the problem of the heat transfer through the multilayer plate was applied. Derived solution connects the temperature of air and temperature on the snow-ice interface and satisfactory correlates with data of the field measurements of the temperature within snow layer and ice cover and ice thickness on the Heilongjiang （Amur） River. Results of investigation are recommended for the ice temperature evaluation in engineering practice.

Method of Judging Potential Failure States of Electronic Instruments

Potential failures of electronic instrument are very common in the engineering practice.In this paper,potential failure state model is analyzed based on dynamic characteristics of electronic instrument at work and a comprehensive method of judging multi-state reliability is put forward.Then,a multi-state electronic instrument reliability analysis model is built based on Bayesian Networks(BN).Considering the failure-potential failure-normal work states,the model is built to estimate reliability of the system and the conditional probability of the elements.Finally,the model is proved corrective and effective by examples.

Sixty years of engineering blasting in China： Review and prospect

Based on representative blasting engineering examples,the development history of engineering blasting in China since 1950 s was reviewed,three development phases were summarized,and the main achievements of fundamental theory,engineering practice,scientific study and industry organization of engineering blasting in each phase were introduced briefly.Finally,some suggestions about the development direction of engineering blasting in China were given.