Application of LRB isolation technology in continuous girder bridges

This paper summarizes the superiority of lead-rubber beating （LRB） continuous girder bridges. The research method for isolation performance is discussed when pile-soil interaction is considered. By the finite element method and self-compiling program, a systematic study of the reliability of LRB continuous girder bridges is given by the use of different indicators, including the riding comfort of the LRB system, the pounding and dynamic stability when the LRB system is subjected to seismic excitations, and the reliability of the LRB system when subjected to other common horizontal loads. The results show that the LRB system has obvious advantages over the traditional continuous girder structure. The LRB isolation effect remains good even when pile-soil interaction is considered; the vertical rigidity of the LRB guarantees desirable riding comfort. The LRB demonstrates good reliability when subjected to the effects of braking, wind loads and temperature. However, it is also pointed out that the pounding of the LRB system subjected to earthquakes must be avoided, and the dynamic stability may be reduced when the LRB system has higher piers and generates a larger displacement in a strong earthquake. Useful advice and guidance are proposed for engineering application.

Seismic Reduction and Isolation Design Strategies for Bridges in High-Intensity Earthquake Areas

High-intensity earthquakes can cause severe damage to bridges,buildings,and ground surfaces,as well as disrupt human activities.Such earthquakes can create long-distance,high-intensity surface movements that negatively impact bridge structures.This article delves into the seismic reduction and isolation design strategies for bridges in high-intensity earthquake areas.It analyzes various seismic reduction and isolation technologies and provides case studies to help relevant units understand the design strategies of these technologies.The results of this article can be used as a guideline to effectively enhance the seismic performance of bridges in high-intensity earthquake areas.

Separation and analysis of six fractions in low temperature coal tar by column chromatography

The low temperature coal tar(CT)is taken as the raw material,and the extraction and column chromatography are used for detailed and accurate characterization in this paper.The n-heptane soluble fraction(CT-HS)and insoluble fraction(CT-HI)were obtained by n-heptane Soxhlet extraction.The extraction rate of CT-HS reached 92.79%(mass),which indicated that there are few heavy compounds in it.Further,different solvents(methylbenzene,benzene,ethyl acetate,methylbenzene-ethanol)were used to elute CT-HS by chromatographic column to obtain five fractions(saturates,aromatics,heteroatoms,phenolics and resins,named CT-SA,CT-AR,CT-HE,CT-PH,CT-RE,respectively).The yields of CTSA,CT-AR,CT-HE,CT-PH,CT-RE are 42.12%,10.43%,2.19%,9.50%and 6.63%(mass),respectively.Gas chromatography-mass spectrometry analysis of eluting components show that alkanes are the main components in CT,followed by polycyclic aromatics,and the corresponding fractions are CT-SA and CT-AR,respectively.The relative content of aliphatics in CT-SA is 76.93%,and the relative content of aromatics in CT-AR is 75.05%.This separation technology effectively separates and enriches different components in CT,and the activation energy required for the pyrolysis process of a single eluting fraction is lower than that of CT,which is expected to provide an important reference for the separation,analysis and conversion of complex oil products such as coal-oil co-processing products,coal tar and other complex heavy carbon oil products.

Reduction of structural response to near fault earthquakes by seismic isolation columns and variable friction dampers

This paper focuses on the investigation of a hybrid seismic isolation system with passive variable friction dampers for protection of structures against near fault earthquakes. The seismic isolation can be implemented by replacing the conventional columns fixed to the foundations by seismic isolating ones. These columns allow horizontal displacement between the superstructure and the foundations and decouple the building from the damaging earthquake motion. As a result, the forces in the structural elements decrease and damage that may be caused to the building by the earthquake significantly decreases. However, this positive effect is achieved on account of displacements occurring in the isolating columns. These displacements become very large when the structure is subjected to a strong earthquake. In this case, impact may occur between the parts of the isolating column yielding their damage or collapse. In order to limit the displacements in the isolating columns, it is proposed to add variable friction dampers. A method for selecting the dampers＇ properties is proposed. It is carried out using an artificial ground motion record and optimal active control algorithm. Numerical simulation of a sevenstory structure shows that the proposed method allows efficient reduction in structural response and limits the displacements at the seismic isolating columns.

Capillary Zone Electrophoretic Separation of Basic Proteins with Coated Columns Prepared by Sol-Gel Technology

Coated capillary columns were prepared by sol-gel technology and used in the separation of basic proteins with capillary zone electrophoresis. The results indicated that a significant decrease in protein adsorption was obtained and EOF was also diminished to zero in the pH range of 3-10.

A rapid and cost effective protocol for plant genomic DNA isolation using regenerated silica columns in combination with CTAB extraction

Isolation of high quality DNA from multiple samples can be both time-consuming and expensive. We have developed a combined protocol to reduce the time component of the hexadecyltrimethylammonium bromide （CTAB） extraction method and reduced costs by regenerating the silica columns used to purify genomic DNA. We present data that shows, by in- creasing the temperature used during the CTAB method, the time required to extract crude genomic DNA can be reduced. We show that silica columns can be regenerated using HCI and still maintain their DNA-binding capacity. Furthermore, we show both spectrophotometrically, and by restriction enzyme cutting, that the quality of the eluted DNA is high. Critically, using both genomic DNA from pea and perennial ryegrass we demonstrate, using species-specific PCR primers, that there is no carry-over of DNA from repeated use of a single column. The main advantages of the method are high yield, high quality, cost effectiveness and time-saving. This method could satisfy demand when large numbers of plant genomic DNA samples are required, for example from targeting induced local lesions in genomes （TILLING） populations.

Blockchain and IIoT Enabled Solution for Social Distancing and Isolation Management to Prevent Pandemics

Pandemics have always been a nightmare for humanity,especially in developing countries.Forced lockdowns are considered one of the effective ways to deal with spreading such pandemics.Still,developing countries cannot afford such solutions because these may severely damage the country’s econ-omy.Therefore,this study presents the proactive technological mechanisms for business organizations to run their standard business processes during pandemic-like situations smoothly.The novelty of this study is to provide a state-of-the-art solution to prevent pandemics using industrial internet of things(IIoT)and blockchain-enabled technologies.Compared to existing studies,the immutable and tamper-proof contact tracing and quarantine management solution is proposed.The use of advanced technologies and information security is a critical area for practitioners in the internet of things(IoT)and corresponding solutions.Therefore,this study also emphasizes information security,end-to-end solution,and experimental results.Firstly,a wearable wristband is proposed,incorporating 4G-enabled ultra-wideband(UWB)technology for smart contact tracing mechanisms in industries to comply with standard operating procedures outlined by the world health organization(WHO).Secondly,distributed ledger technology(DLT)omits the centralized dependency for transmitting contact tracing data.Thirdly,a privacy-preserving tracing mechanism is discussed using a public/private key cryptography-based authentication mechanism.Lastly,based on geofencing techniques,blockchain-enabled machine-to-machine(M2M)technology is proposed for quarantine management.The step-by-step methodology and test results are proposed to ensure contact tracing and quarantine management.Unlike existing research studies,the security aspect is also considered in the realm of blockchain.The practical implementation of the proposed solution also obtains the results.The results indicate the successful implementation of blockchain-enabled contact tracing and isolation management using IoT and geo-fencing techniques,which could help battle pandemic situations.Researchers can also consider the 5G-enabled narrowband internet of things(NB-IoT)technologies to implement contact tracing solutions.

Earthquake Response and Isolation Layer Parameter Effect of Seismic Isolation Systems of Transformers With Bushings

国内外震害表明，变压器在地震中的破坏型式多样，易损性极高。隔震技术是一项能够有效降低地震反应的新型抗震技术，而变压器及套管隔震层的设计和参数选择与普通结构有较大的差异。首先，建立了大型电力变压器及套管隔震体系的多质点分析模型，采用Matlab软件编写计算程序，分别输入人工地震波和Taft地震波，对变压器及套管隔震体系的地震响应进行分析；最后，开展了隔震层等效水平网0度、等效阻尼比、双线性恢复力模型的屈服剪力系数及屈服后刚度等参数的地震响应影响分析。分析结果表明：合理设计变压器及套管隔震体系的隔震层参数，可有效降低变压器及套管的地震响应；另外，通过隔震层的参数分析，得到了相关参数的合理取值范围。该研究对今后变压器及套管隔震体系的设计具有参考与指导作用。

基于第三方库隔离的Python沙箱逃逸防御机制

PaaS平台由于可提供Python服务成为目前较受欢迎的云服务。PaaS平台应用Python沙箱解决安全问题,同时允许用户使用Python C化模块以降低Python对性能的影响。然而,攻击者能够利用Python沙箱策略的漏洞进行逃逸,导致危害底层系统。现有的Python沙箱大多在代码层进行防御,缺乏对Python C化模块的监管和防护。文章分析了Python C化模块的底层原理和Python沙箱逃逸的特点,针对沙箱逃逸后需要执行特定危险函数发起攻击的特征,提出一种基于第三方库隔离的Python沙箱逃逸防御机制,并实现了原型系统。该机制的原型系统利用GOT Hook技术对Python的C化模块导入行为和危险函数调用行为进行接管,在Python导入C化模块时,提前对该C化模块进行安全检查和隔离。另外,在Python调用危险函数时,对该函数的参数进行检查。实验结果表明,文章所提机制能够有效防御攻击者利用自定义的C化模块逃逸Python沙箱以及使用恶意参数调用危险函数。在正常使用时,文章所提机制的时间开销较低,平均时间开销小于5%。

Isolation and Identification of Flavone Type of Two Compounds from Salix matsudana

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Bubble Column Reactor Fluid-dynamic Evaluation at Pilot-plant for Residue and Extra-heavy Crude Oil Upgrading Technology

Bubble column reactors are multiphase contacting devices used in a wide variety of industrial application. Inrtevep S. A. is working on developing technologies to convert heavy and extra-heavy crude oil using this type of reactors. Volumetric gas hold up, flow pattern, average gas bubble size, average interfacial area, RTD （residence time distribution）, dispersion coefficient, Peclet number are important design parameters for a proper scale up of them. Several cold model experiments have been proposed to determine the previously mentioned parameters at atmospheric conditions, using a plexiglas bubble column reactor at pilot plant scale unit （12 cm diameter）. It was also evaluated our own design of internal trays （plates） in the reactor. Air-tap water and air-light oil systems have been used. A wide operating condition range was applied, superficial gas velocity between 0.5-10 cm/s, liquid flowrate between 15-65 I/h. Generally speaking, working without internal trays was found that gas hold up increase along the reactor and it was possible to identify heterogeneous bubble, transition and turbulent flow pattern areas for the air-light oil system. Average gas bubble size increase along the reactor at bubble regime from 2-5 mm but at turbulent regime, stay oscillating between 1-3 mm. Average interfacial area increases exponentially with superficial gas velocity at any reactor height, till 1,412 m2/m3 for the air-light oil system but, at bubble flow regime, the average interfacial area is lower than 100 m2/m3, which negatively impact the reactor performance. Internal trays in the reactor always increase gas hold up at any condition or system used. Residence time distributions curves, Peclet numbers and dispersion coefficients founded, show that this reactor with this kind of design internal trays still tends to be a complete mixing reactor under the operating conditions used.

Describe the Process of Retrofitting Existing Buildings and Evaluate the Effectiveness of it in Improving the Seismic Performance of Structures in Earthquake-prone Regions

At present,earthquakes are a serious problem for building.Severe damages and collapses of buildings were caused by earthquakes in different degrees.It is reported that there are more than 68,858 deaths and hundreds of billions RMB losses in the May 12,2008 Great Wenchuan Earthquake[16].So,more attention should be paid to seismic technology.In order to face the challenges of earthquake on building,the seismic retrofitting was put forward,which“is the modification of existing structures to make them more resistant to seismic activity,ground motion,or soil failure due to earthquakes”[2].

Isolation Scanner套后成像测井找漏技术在H油田的应用

塔里木盆地H油田整体采用超深水平井开发,近年套损现象呈增加趋势。目前常用套损井找漏技术效果不理想。针对该现状提出了Isolation Scanner套后成像测井(IBC)找漏技术,该技术能同时测量套管内径和壁厚变化,定量评价内部腐蚀和外部腐蚀,分辨率高,在H油田H68水平井应用成功,该技术为H油田类似油水井找漏提供了技术指导和实际经验。

Novel design of lubricant-type vacuum distillation process for lube base oils production from hydrocracking tail oil

Dividing-wall columns(DWCs)are widely used in the separation of ternary mixtures,but rarely seen in the separation of petroleum fractions.This work develops two novel and energy-efficient designs of lubricant-type vacuum distillation process(LVDP)for the separation of hydroisomerization fractions(HIF)of a hydrocracking tail oil(HTO).First,the HTO hydroisomerization reaction is investigated in an experimental fixed-bed reactor to achieve the optimum liquid HIF by analyzing the impact of the operating conditions.A LVDP used for HIF separation is proposed and optimized.Subsequently,two thermal coupling intensified technologies,including side-stream(SC)and dividing-wall column(DWC),are combined with the LVDP to develop side-stream vacuum distillation process(SC-LVDP)and dividing-wall column vacuum distillation process(DWC-LVDP).The performance of LVDP,SC-LVDP,and DWC-LVDP are evaluated in terms of energy consumption,capital cost,total annual cost,product yields,and stripping steam consumption.The results demonstrates that the intensified processes,SC-LVDP and DWC-LVDP significantly decreases the energy consumption and capital cost compared with LVDP.DWC-LVDP further decreases in capital cost due to the removal of the side stripper and narrows the overlap between the third lube oils and fourth lube oils.This study attempts to combine DWC structure into the separation of petroleum fractions,and the proposed approach and the results presented provide an incentive for the industrial implementation of high-quality utilization of HTO through intensified LVDP.

Introduction to steel pylon hoisting of Taizhou Yangtze Bridge

Taizhou Yangtze River Bridge is the first three-pylon two-span suspension bridge in the world. The middle pylon adopts deep water caisson foundation. The superstructure of the middle pylon employs herringbone shape along the bridge, and portal shape in the transverse direction for the first time in China. In this paper, the basic construction procedure, equipment, construction steps, the key construction technologies and methods of steel pylon are introduced.

Simulation and heat exchanger network designs for a novel single-column cryogenic air separation process

To realize the industrialization of the novel single-column air separation process proposed in previous work,steady-state simulation for four different configurations of the single-column process with ternary(nitrogen,oxygen and argon)is developed.Then,exergy analysis of the single-column processes is also carried out and compared with the conventional double-column air separation process at the same capacity.Furthermore,based on the steady-state simulation of single-column processes,the different heat exchanger networks(HENs)for the main heat exchanger and subcooler in each process are designed.To obtain better performance for this novel process,optimization of process configuration and operation is investigated.The optimal condition and configuration for this process is consisted as:feedstock is divided into two streams and the reflux nitrogen is compressed at the approximate temperature of 301 K.In addition,HEN is optimized to minimize the utilities.HENs without utilities are obtained for the four different configurations of single-column process.Furthermore,capital costs of the HEN for different cases are estimated and compared.

互联网使用对老年人社会适应的影响与作用机制

互联网使用对老年人的社会适应产生重要影响,但关于有何影响及如何影响的研究较少,且多数研究聚焦于互联网技术本身,忽视了作为技术使用主体的老年人的“能动性”。基于中国老年社会追踪调查(CLASS2018)数据,参考相关经典理论,发现相比不使用互联网的老年人,使用互联网的老年人的社会适应水平更高,老年人使用互联网的频率越高,其社会适应水平也越高。此外,在互联网使用对老年人社会适应产生影响的过程中,社会参与发挥着正向中介作用。因此,实现积极老龄化不仅需要鼓励老年人主动触网,促进老年人的数字融入、消除数字鸿沟,还要利用互联网不断增进老年人的社会参与。

PDCA循环对提高腹腔镜下胃癌根治术中隔离技术执行率的应用研究

目的研究PDCA循环对提高腹腔镜下胃癌根治术中隔离技术执行率的应用效果。方法组建护理质量持续改进小组,选定活动主题为提高腹腔镜下胃癌根治术中隔离技术执行率,调查2022年10月16日至2023年3月11日在我院手术室开展腹腔镜下胃癌根治术的手术患者共84例,针对导致术中隔离技术执行率低的原因进行分析,拟定对策并实施,效果确认后列为隔离技术质量标准。结果通过这期PDCA活动,腹腔镜下胃癌根治术中隔离技术执行率由实施前的67.8%提高至91.7%(P<0.001);器械摆台规范率由78.0%提高至97.0%(P<0.001);医生满意度评分由(82.0±3.7)分提高到(98.1±4.0)分。结论PDCA活动提升了手术室护士腹腔镜手术隔离技术的执行率,促进了手术室亚专科手术配合中隔离技术的发展,得到了满意的手术治疗效果。