bluuebunny/crossref_metadata_2025 huggingface dataset:
Highly electroconductive and uniform WS2 film growth by sulfurization of W film using diethyl sulfide
Authors: Lee Yoobeen , Jung Jin Won , Lee Jin Seok
Published: March 2021

The reduction of intrinsic defects, including vacancies and grain boundaries, remains one of the greatest challenges to produce high-performance transition metal dichalcogenides (TMDCs) electronic systems.
Temperature assistance of electric field-controlled spin–orbit torque-based magnetization switching in PMN–PT/FePt heterostructures
Authors: Guo Qi , Wang Zhicheng
Published: March 2021

E-field has an improved regulating effect on PMA and SOT-based current induced magnetization switching of PMN–PT/FePt heterostructures.
Improving quantum efficiency in organic solar cells with a small energetic driving force
Authors: Liu Haiqin , Li Mengyang , Wu Hongbo , Wang Jie , Ma Zaifei , Tang Zheng
Published: March 2021

The quantum efficiency of the organic solar cell with a small driving force can be increased by using a second donor with the chemical structure similar to the primary donor, while the low voltage loss of the solar cell is very well maintained.
High-temperature, thin, flexible and transparent Ni-based heaters patterned by laser-induced reductive sintering on colorless polyimide
Authors: Nam Vu Binh , Shin Jaeho , Choi Ahyoung , Choi Hoimyung , Ko Seung Hwan , Lee Daeho
Published: March 2021

A novel method for the fabrication of high-temperature, lightweight, flexible and transparent Ni-based heatersviathe laser digital patterning process of solution-processed NiOxnanoparticle thin films on colorless polyimide has been developed.
Reservoir prediction of shallow braided delta front by Comprehensive Prediction Error Filtering Analysis
Authors: Li Wenjuan
Published: March 2021

For a more accurate reservoir prediction of braided delta front, the method of High Resolution Sequence Stratigraphy was adopted in Moxizhuang Oil Field with the assistance of Comprehensive Prediction Error Filter Analysis. J1s2 was divided into 2 fifth-order base-level cycles, 5 sixth-order base-level cycles, with the turnaround surfaces of base-level rise to fall, and time-equal correlation of shallow braided delta front was achieved. Through study of microfacies correlation in High Resolution Sequence Stratigraphy frame, it is apparent that base-level cycles control microfacies distribution, and furthermore reservoir distribution: reservoirs around turnaround surface of base-level falling to rising are thick and laterally connected, while reservoirs near the middle of base-level falling and base-level rising are relatively thinner and less laterally connected, and reservoirs close to the beginning of base-level falling and the end of base-level rising are undeveloped.
Research on Key Technologies of Virtual Simulation Modeling for Switch Machine
Authors: Zhao Yang , Wang XiangWei
Published: March 2021

In order to improve the training effect, according to the mechanical structure of switch machine, combined with unity3D engine, a set of automatic learning system for switch machine based on virtual reality technology is designed. It realizes the guided teaching of switch equipment ,such as structure composition, three-dimensional model demonstration of action process and virtual disassembly. The system significantly improves the quality of training.
Fault diagnosis of electric submersible pump tubing string leakage
Authors: Yang Jiali , Li Wei , Chen Jiarui , Sheng Li
Published: March 2021

With the rapid development of the offshore oil industry, electric submersible pumps have become more and more important. They are the main pumping equipment in oil well production and have huge advantages in terms of displacement and production costs. Due to the complex structure of the electric submersible pump, the bad working environment will cause failures. The failure of tubing string leakage is a common failure in oilfields; tubing string leakage of the electric submersible pump will reduce oil production. In order to reduce the economic loss of oil well production. This paper uses PCA and Mahalanobis distance to make the tubing Fault diagnosis of leakage. The feasibility of the algorithm is verified through experiments. The result shows that it can diagnose the failure time of pipe string leakage in advance and hence help us to reduce the maintenance cost of offshore oilfields.
Study on Testing Methods for the Heat Transfer Performance of Plate Heat Exchangers
Authors: Ren Bin , Zhu Xuchen , Du Yannan , Pu Zhe , Lu Hongliang , He Aini
Published: March 2021

Plate heat exchangers are new-type compact heat exchangers with high heat transfer efficiency widely used in heating, food, medicine, shipbuilding and petrochemical industries. However, only the laboratory testing can accurately obtain the real heat transfer and flow resistance performance of plate heat exchanger. In this paper, the basic principles of modified Wilson plot method and equal velocity method are firstly introduced. Then the testing system including flow chart and testing instruments are discussed. Finally, contrast experiments using the different two methods are conducted. The results showed that for plate heat exchangers with equal channel, the equal velocity method and modified Wilson plot method can both be used to test the convective heat transfer performance of plate heat exchanger. The equal velocity method is recommended because the deformation of plate is relatively smaller.
Research on Localization of Serpentine Tube High Pressure Heater
Authors: Zhu Xuchen , Du Yannan , Ren Bin , Tang Xiaoying
Published: March 2021

It could be seen that the ultra supercritical reheating is a high-end technology in the field of power equipment manufacturing, which represents the strength and design level of national major equipment manufacturing industry. Based on the development of key components technology of millions of secondary reheat units, solving the design and manufacturing problems of serpentine high-pressure heater, optimizing the heat exchange efficiency of serpentine high-pressure heater, and improving the operation reliability, will help to promote the development process of China’s high-end power equipment, and provide important technical support for the quality supervision and management of serpentine high-pressure heater.
Research on the impact of coal miners’ workload on unsafe behaviors
Authors: Feng Taozhu , Ren Yingsha
Published: March 2021

Workload is one of the reasons that affect unsafe behavior in coal mines. This article divides workload into six dimensions: physical demand, mental demand, time demand, performance level, effort level and frustration level, and introduces miner emotions as an intermediary variable to study the impact of workload on unsafe behavior. Through a questionnaire survey of coal mine workers, a structural equation model of coal mine workers’ workload and unsafe behavior is constructed. The results show that the six dimensions of workload have a significant impact on emotions. Physical demand, mental demand, time demand and frustration level have a significant impact on unsafe behaviors. Performance level and effort level have no significant impact on unsafe behaviors.
Path analysis of influencing factors of completeness evaluation in Sanyizhai Irrigation Area
Authors: Feng Feng , Ting Zhao , Nan Jiang , Fang Zhang , Mengzhen Wang , Yuehua Feng
Published: March 2021

Completeness are comprehensive evaluation of the development status of irrigated areas. The study of their main influencing factors can provide strong data support for the high-quality development of irrigated areas. The paper choose the data during 2005 to 2014 of Sanyizhai Irrigation Area as analysis samples, clear different key factors affecting the evaluation target, in which six factors equal, according to different evaluation subjects and goals, the same impact factor of direct effect and indirect effect, decision coefficient and significant contribution to total R2. For the comprehensive completeness of Yellow River Sanyizhai Irrigation Area, the channel length is the most important influencing factor. The actual irrigation area, mechanism setting and channel lining rate have a significant influence on the comprehensive completeness evaluation of Yellow River Sanyizhai Irrigation Area, while the direct effect of the actual water amount is the least. Compared with the simple correlation coefficient and regression analysis method, the path analysis method can accurately calculate the direct and indirect effects of the independent variables on the dependent variables, which has the advantages of intuitive, scientific and reasonable. According to the analysis results, it can make clear the direction of efforts for the upgrading and transformation of the irrigation area and the development of high quality.
Discussion on construction scheme of aqueduct structure repair and water stop belt replacement in South-to-North Water Diversion project
Authors: Jao Kang , Li Jian , Liu Jianshen , Zhou Zhiyong , Cheng Haihua
Published: March 2021

Taking Shahe and Dalang River aqueducts as an example, this paper introduces a movable and reusable waterproof device for aqueduct construction, which is suitable for construction scheme of structure repair and waterstop belt replacement for large-scale water delivery aqueduct of Shahe River and Dalang River in South-to-North Water Diversion Project. It aims to solve structural damage and waterstop belt leakage of the aqueducts of Shahe River and Dalang River in the South-to-North Water Diversion Project, realizing the aqueduct construction with uninterrupted water supply, and structure repair and waterstop belt replacement in the waterless environment separated by watertight device in the aqueduct construction.
Sewage Treatment System Planning for Dianchi Urban Wetland Park in Kunming
Authors: Wu Yan-Sheng , Li Yan , Gao Xiong , Pan Jie , Wang Ning , Cheng Yong-Wei , Yang Cong-Gao , Yang Ya-Chao
Published: March 2021

Dianchi Lake urban wetland park in Kunming is an important component of Dianchi lakeside wetlands, it is of great significance to the urban development and ecological protection of Kunming. To solve the problem of non-point source pollution of Dianchi Lake basin, the Dianchi Lake Pan-Asian International Urban Wetland Park is taken as an example, the rapid artificial infiltration treatment system and the comprehensive constructed wetland treatment system were designed for Dianchi Lake urban wetland park, and various design parameters and its influencing factors have been analyzed. After the deep treatment by the treatment system, the water quality reached the standards of landscape water. The planning of water system for Dianchi Lake urban wetland park provides a reference for designing plateau lake urban wetland parks.
Pastures planting can ease the conflict between free-range chicken production and the stocking environment
Authors: Yu Chunlin , Yang Chaowu , Du Huarui , Qiu Mohan , Li Qingyun , Peng Han , Zhang Zengrong , Song Xiaoyan , Xiong Xia , Xia Bo , Hu Chenming , Yang Li , Chen Jialei , Du Longhuan , Jiang Xiaosong
Published: March 2021

The introduction of forage grass in poultry industry had double benefit on animals and the environment. In this study, three kinds of pastures were planted artificially to evaluate their roles through the determination of grass, chicken and soil-related indexes. The results showed that raising chickens under the forest could destroy vegetation and affect the chemical properties of soil negatively. Changes of soil caused by chickens can be alleviated through planting grass. Forage provided a certain food source for chickens without affecting the growth, slaughter properties, meat quality, immune indexes and other performances. Suitable pasture should have good regeneration ability, trampling resistance, good palatability, and do not cause harm to the health of chickens.
Trouble Of Vespa Mandarinia: Confirming the Buzz about Hornets
Authors: Zhiquan Wang
Published: March 2021

In order to help Washington State interpret the data about Vespa mandarinia provided by the public report, and enable government agencies to adopt corresponding strategies to prioritize correct reports when resources are limited, for further investigation, this article establishes two targeted models: The first unsupervised probability prediction model. First, extract the text information of misjudgment classification in the data set, and carry out preprocessing. The data set is divided into training set and test set according to the ratio of 8:2, and the Latent Dirichlet Allocation model is trained using the misjudgment classification information in the training set. After the model training is completed, this paper makes a probability prediction on the data on the test set, and evaluates the robustness of the model through the accuracy rate on the test set. The second text similarity matching model is based on feature dimensionality reduction and extracting feature keywords as vectors. The TF-IDF algorithm is used to calculate the weight of each feature keyword in the vector to form a standard bag-of-words vector for the correct witnessing of the Vespa mandarinia report. Judge by the similarity of text similarity matching model.
Synthesis of Mesoporous Silica Nanowires and Their Application in Enzyme Immobilization
Authors: Liu Peng , Liu Xinlong , An Na , Wang Peng
Published: March 2021

Hydrophobic mesoporous silica nanowires were synthesis and then employed as support for immobilization of lipase from Candida antarctica via covalent bonding (CALB@MSW). The parameters were optimized and the optimum conditions were as follows: GA concentration 5.5 wt.%, activation time 60 min and CALB concentration 4 mg/mL. Under these conditions, the protein loading and specific activity of CALB@MSW were 138.3 mg/gsupport and 41.1 U/mgsupport, respectively. Compared with free CALB, CALB@MSW showed better thermal stability and pH stability. The maximum yield of biodiesel catalytic by CALB@MSW was 93.4 %. After reused 8 times, CALB@MSW still remained 95.75 % initial activity showing better stability than free CALB.
Optimization of SOFC stack gas distribution structure based on BP Neural network and CFD
Authors: Zhang Yuhao , Xiong Xingyu , Wu Xin , Song Zhonghui , Xue Zhenzhong
Published: March 2021

The flow field distribution of solid oxide fuel cells significantly affects the performance of the stack. The flow uniformity can be improved and the power generation efficiency can be improved by optimizing the gas distribution structure of the stack. Based on the simplified 6kW stack model, the stack gas distribution structure with two-stage buffer cavity was designed, and the stack model was numerically simulated by ANSYS Fluent software. The BP neural network model, which can predict the uniformity of the outlet of the integrated stack, is established successfully. The parameters of the gas distribution structure are analyzed and optimized by using the orthogonal test and BP neural network. The results show that at the same time considering pile distribution structure under the condition of surface area and uniformity, when the first stage inlet buffer chamber depth is 40 mm, the channel width is 40 mm, the secondary inlet buffer chamber depth is 80 mm, can effectively reduce the electric pile distribution structure, surface area, to reduce heat loss, at the same time guarantee the integrated electric reactor outlet flow uniformity of more than 96%, greatly improves the efficiency of power generation.
Study on mechanical properties and microstructure of DP590 steel with different annealing process
Authors: Pan Libo , Lin Chengjiang , Zhou Wenqiang , Zuo zhijiang
Published: March 2021

Annealing process is critical to mechanical properties and microstructure of DP steel. For DP steel with strength grade of 590MPa, experiments with different combinations of intercritical annealing temperature and over-aging temperature were carried out during annealing. The tensile tests of the final products and nanohardness tests of different phases were made, and the microstructures were analyzed. The results indicated that higher intercritical annealing temperature was favorable to higher volume fraction of martensite and lower nanohardness of martensite with lower C density. The ultimate tensile strength increased monotonously with the volume fraction of martensite increasing. Higher over aging temperature would make martensite islands be partially resolved and carbides precipitate, which made lower volume fraction of martensite, and resulted in lower nanohardness of martensite. The revealed rules could provide important guide to control material properties of DP steel by manipulating annealing process.
Construction of C/MoS2 nanocomposite for highly efficient electrocatalytic NRR
Authors: Guohua Yang , Nan Li
Published: March 2021

Electrochemical N2 reduction reaction (NRR) has been considered as a promising and green process to replace conventional Haber−Bosch process. However, the presence of sluggish reaction kinetics and competitive hydrogen evolution reaction (HER) can result in poor activity and unsatisfactory selectivity. Here, we proposed C/MoS2 catalysts by a facile ‘one-pot’ hydrothermal method. Benefiting from porous nanosphere structure, it shows outstanding charge transfer rate, which accelerates NRR kinetics. As a result, C/MoS2 exhibited a conspicuously improved NRR performance with a high Faradaic efficiency (FE) of 8.2% at −0.7 V. In addition, this electrocatalyst showed marvelous stability.
Review: Developments of Photovoltaic/thermal (PVT) Collectors
Authors: Wang Qixian
Published: March 2021

The alarming energy concerns have stimulated a transition of energy sources to a more sustainable way. Among all of the green energy sources, solar is the most promising one. Recently, a new application called photovoltaic/thermal panels that harvest both long-wavelength and short-wavelength radiations has been gaining attention. Evidence shows that the combined system is more efficient than the two separate systems. Its wide range of applications can significantly promote the transition to a cleaner energy source. This work provides an introduction to the PV/T panels and examines the improvement possibilities of the PV/T panels. Challenges and suggestions for future researches will be discussed.
Research on the thermal hazard of N-Nitrodihydroxyethyl dinitrate (DINA) under the action of diethanolamine
Authors: Li Yuehua , Liu Yu , Chen Liping , Wu Wenqian , Zhao Xiaoqiao , Chen Wanghua
Published: March 2021

N-Nitrodihydroxyethyl dinitrate (DINA) is a commonly used energetic material. In this work, the effect of diethanolamine (DEA) on the thermal stability of DINA was studied. Firstly, the decomposition kinetics of DINA under the influence of DEA was analyzed by applying dynamic differential scanning calorimeter (DSC) experiments. Then, isothermal DSC tests with the “Interruption and re-scanning” method determined that the decomposition reactions of DINA containing 29% DEA consists of four continuous steps: the first step is a n-order reaction, and the last three steps are autocatalytic reactions. The kinetic parameters of the four-step reaction model were calculated by model-fitting method. Finally, the thermal risk parameter like TMRad was predicted based on the kinetic parameters, which has certain guiding significance for the process production of DINA.
Research on the Construction of Ideological and Political Teaching Team of College Courses Based on Competency
Authors: Zhang Nan
Published: March 2021

Strengthening the construction of the ideological and political teaching team in the course of ideological and political teaching in colleges and universities can improve the level of ideological and political teaching in a certain degree. In the course of curriculum ideological and political implementation, there are new requirements for the various abilities of college teachers. Under this circumstance, teachers should study and analyze the construction of college curriculum ideological and political teaching team from the perspective of competency model based on curriculum ideology and politics. This article discusses the professional quality of ideological and political course teachers under the requirements of mastering the competency model and the relevant strategies for constructing the ideological and political teaching team of college courses. This article aims to improve the level of ideological and political teaching team building in colleges and universities.
The Effects of Prize and Scheduling Strategies in Crowdsourcing activities
Authors: Su Xiaohui , Feng Xiaoliang , Peng Leiqing
Published: March 2021

Crowdsourcing provides an efficiency mode to explore crowd knowledge resource. It can provide diverse solutions for problem solving. However, how to design crowdsourcing strategies to drive crowd to participate in crowdsourcing activities is the focus of crowdsourcing platform management. Extant research mainly concentrated on prize strategy whereas little attention has been paid to scheduling strategy. Yet holistic crowdsourcing strategy should incorporate both scheduling strategy and prize strategy. Based on motivation incentive theory, this research applied over 154 thousand crowdsourcing projects’ secondary data to examine the impact of crowdsourcing strategy. Both prize strategy and scheduling strategy have a positive effect on the number of participants. Furthermore, there is a positive interaction effect between prize and scheduling. These findings can enrich crowdsourcing theory and provide implications in crowdsourcing strategy design.
Study on construction site Safety Management from the perspective of learning organization theory
Authors: Fazhong Shi , Wenyin Shi
Published: March 2021

Safety is the basis of all production and living behaviors, and is an important guarantee for the safety of employees’ lives and enterprises’ property. This study focuses on the construction site safety management as the research object, and analyzes the current situation and shortcomings of the construction site safety management. This paper tries to explain the deep causes of the current situation by the theory of learning organization, and gives some suggestions to further improve the safety management of the construction site.
Prediction of an epidemic with Machine Learning and Covid-19 Data
Authors: Wenhui Fang , Yihui Wang , Zhipeng Lu
Published: March 2021

The human race has already overcome many epidemics such as smallpox, SARS, and Black Death with vaccines or cures. As the number of infected people climes up to 10 million due to the new coronavirus in 2020, the human race faced another public health challenge. Because of the strong infectivity of the new coronavirus, humans have not won this fight after half a year. During the times of defeating these viruses, humans sacrificed not only wealth but also lives. Apart from many tribulations, human race also has great development in on technology. Machine learning method was invented and applied in many fields such as robotics, healthcare, and medicine. Since the transmission of a virus is related to social factors such as the percentage of college degree, and population density, there is a model built in this article that only related to outside factors such as health insurance coverage to predict that when the climax of an epidemic will arrive by using machine learning techniques and data related to Covid-19. Since the model does not take transmissibility of one specific virus, this model can apply to any epidemics to forecast the peak with enough data.
Research Progress on Tissue Engineering of Main Tissues and Organs of Human Body
Authors: Jin Zhirui
Published: March 2021

The injury and failure diseases of human tissues and organs, such as heart failure and chronic kidney disease, seriously threaten human health and life safety. At present, however, organ transplantation has obvious limitations, and tissue engineering is considered as a potential alternative therapy. Tissue engineering uses the construction of cells, biomaterials and bioreactors to develop three-dimensional artificial tissues and organs for the enhancement, repair and replacement of damaged or diseased tissues and organs, which contributes to the fundamental solutions of diseases of tissues and organs as well as to the improvement of human health. This paper introduces the research progress of tissue engineering technology in the field of living organs from three aspects: seed cells, application of growth factors and biomimetic preparation of functionalized scaffold materials, hoping to provide help and ideas for the research and industrial development of the repair and reconstruction of human organs.
Study on the mechanism of Erzhi Pill in the treatment of breast cancer based on network pharmacology
Authors: Yuan Fahu , Liao Xinghua , Zhang Tongcun
Published: March 2021

Objective: To explore the possible mechanism of Erzhi Pill in the treatment of breast cancer based on network pharmacology. Methods: Through systematic pharmacology database and analysis platform of Traditional Chinese medicine (TCMSP) and literature review, the candidate active ingredients and corresponding targets of Erzhi Pill were retrieved and collected. The UniProt database and the Human Genome Annotation Database (Genecards) were used to compare the results, and the potential target genes were obtained for the coincidence of Erzhi Pill and breast cancer. Cytoscape was used to construct the “candidate component - action target” network of Erzhi Pill. Generate Style from Statistics tool in String database and Cytoscape software was combined to construct protein interaction network.The Kyoto Encyclopedia of Genes and Genomics (KEGG) pathway enrichment analysis and GO classification enrichment analysis for targets of Erzhi Pill were conducted using the Database for Annotation, Visualization and Integrated Discovery (DAVID ) bioinformation resource Database. Results: A total of 21 candidate active components, including Beta-sitosterol, Quercetin, Luteolin, Demethylwedelolactone, Kaempferol and so on, were screened from Erzhi Pill, corresponding to 158 target genes, including vascular endothelial growth factor (VEGF), amino-terminal kinase (C-Jun), proto-oncogene (C-MYC), matrix metalloproteinase-9 (MMP-9), and mainly involved in TNF-α, phosphatidylinositol-3-kinase/protein kinase B(PI3K/Akt), tumor suppressor gene p53, toll-like receptor family and other signaling pathways. Conclusion: This study predicted the possible mechanism of action of Erzhi Pill in the treatment of breast cancer based on the method of network pharmacology, and provided a direction for further research.
Optimization of Small Object detection based on Generative Adversarial Networks
Authors: Ruiqiang Zhang , Yu Zeng , Xin Jin
Published: March 2021

Small object detection is one of the fundamental problems in computer vision applications. Existing small object detection techniques usually focus on detecting small objects with multiple scale of features with low efficiency due to high computational cost. In this paper, we investigate small object detection problem based on generative adversarial architecture that utilizes features of small objects. We propose an Optimized Perceptual Generative Adversarial Network (OPGAN) to present more features of small objects. Specifically, the generator of OPGAN learns to present the low-resolution features of the small objects to highly resolved features similar to large objects as input image of the discriminator model. After then, the discriminator of OPGAN computes the generated feature and generates a new perceptual requirement parameter into the model to train the model iteratively. Extensive experiments on the challenging benchmark data sets demonstrate the effectiveness of OPGAN in detecting small objects.
Research on Enterprise Logistics Management under Sharing Mode
Authors: Sun Jie , Sun Liwen
Published: March 2021

Based on the background of the digital age, in order to solve the problem of enterprise logistics management in the sharing economy environment, summarized and put forward from academic research and enterprise practice, there are two core problems that enterprises have insufficient understanding of the sharing economy and insufficient application of the sharing economy model. Further constructed by shared mode of logistics management mode, building procurement, production, storage and sales quadruple logistics information sharing platform. This article focuses on the improvement of the enterprise logistics system under the sharing mode, exploring the design of the top-level sharing platform, building enterprise alliances, and realizing information sharing. In this way, actively promote the research and development of enterprise logistics management in the sharing economy environment.
Discussion and Inspiration of US military information and communication documents
Authors: Shang Chun yong
Published: March 2021

Under the condition of informatization, the writing of information and communication documents should be fast and timely, accurate, concise, safe and confidential. The U.S. military’s information and communication documents are no exception in drafting. Due to the differences in the establishment system, command system and operational concept, the U.S. military’s information and communication documents have their own unique features. The U.S. military’s information and communication documents pay attention to refining, accuracy, different levels of use, standards and specifications. It is very useful to study the US military’s information and communication documents for the preparation of our army’s document.
Study on the 4-ethyl-2(α-methyl benzyl) phenol Extraction-Separation Between Rubidium and Potassium
Authors: Huang Zheng-gen , An Lian-ying , Yi He-yin , Wang Tao
Published: March 2021

More than 92% of rubidium resources on the earth exist in salt lake brine and underground brine. Rubidium in brine coexists with a large amount of potassium with very similar physical and chemical properties, making the extraction technology of rubidium extremely difficult, and a large amount of rubidium resources in brine have not been rationally utilized. Therefore, the development of a new type of high-selectivity rubidium-potassium separation extractant is of great significance to the establishment of efficient separation and extraction technology of rubidium. By modifying the structure of 4-tert-butyl-2-(α-methylbenzyl)phenol, the traditional rubidium extractant, the steric hindrance effect of tert-butyl is reduced and the reaction efficiency of rubidium and extractant is improved. A new extractant 4-ethyl-2-(α-methylbenzyl)phenol was obtained. The thesis carried out the research on the extraction and separation performance of potassium rubidium 4-ethyl-2-(α-methylbenzyl)phenol. The results show that the new extraction agent 4-ethyl-2-(α-methylbenzyl)phenol and potassium rubidium brine are extracted and separated with a ratio of 10:1. The minimum separation coefficient of rubidium potassium can reach 15 or more, showing excellent separation performance ; When the organic phase is composed of 0.8mol/L extractant and D60 solvent oil, the alkalinity of the aqueous phase is 0.5mol/L sodium hydroxide, and the extraction time is 3 minutes, the single-stage extraction rate of rubidium can reach more than 76.0%, rubidium potassium The separation coefficient can reach more than 26. After repeated use, the extraction rate of rubidium can be maintained above 73% and the separation coefficient of rubidium potassium can reach 23, without a significant drop. It provides a new way and idea for the extraction and separation technology of rubidium in high potassium brine.
Preparation of Stearic acid/Diatomite Composite Phase Change Material
Authors: Zong Jianping , Wang Defu , Jin Yanlin , Gao Xing , Wang Xinxin
Published: March 2021

The composite phase change material was prepared via the impregnation method using diatomaceous as the carrier and stearic acid as the phase change material. The effects of diatomite content, temperature, immersion time and pressure on the mass ratio of stearic acid and diatomaceous earth in the composite phase change materials were discussed. The experimental results showed that the optimum conditions for preparing stearic acid/diatomite composite phase change material were immersion temperature of 80℃, socking time of 2 h, diatomite mass fraction of 23.04%, and vacuum degree of 0.03 MPa. Finally, the infrared spectroscopy analysis of stearic acid/diatomite composite phase change energy storage material showed that there is no chemical reaction between stearic acid and diatomite. And they are held together by intermolecular forces.
Selection of chemical phosphorus removal scheme based on Analytic Hierarchy Process
Authors: Wang Ze
Published: March 2021

Chemical precipitation phosphorus removal process can improve the phosphorus removal effect of sewage treatment system to meet the increasingly stringent discharge standards. In order to assist designers in selecting reasonable chemical phosphorus removal schemes, the analytic hierarchy process was applied to quantitatively evaluate each chemical phosphorus removal scheme from four aspects: water treatment effect, operation cost, operation and management difficulty and environmental impact. Finally, combined with an engineering example, the process of analytic hierarchy process quantitative evaluation of chemical phosphorus removal scheme and the method of selecting the optimal scheme are introduced, which provides a reference for the selection of chemical phosphorus removal scheme in engineering.
Studies on the Preparation and Photocatalytic Performance of Bismuth Ferrite
Authors: Wang Xinxin , Dong Yifa
Published: March 2021

Iron oxide and bismuth oxide powder are synthesized by the liquid phase precipitation method. Then a certain proportion of iron oxide, bismuth oxide and sodium chloride are mixed and ground to prepare the bismuth ferrite precursor by the molten salt method. The bismuth ferrite precursors are calcined at different temperatures to obtain bismuth ferrite photocatalyst. By studying the degradation performance of bismuth oxide, iron oxide and bismuth ferrite photocatalysts for methyl orange dyes, the best conditions for the degradation of methyl orange dyes by bismuth ferrite photocatalysts are found. The experimental results show that the bismuth ferrite prepared by calcining at 750°C has the best degradation. Compared with a single oxide, the photocatalytic performance of bismuth ferrite is better.
Maschinenperfusion in der Lebertransplantation – was ist möglich und wo stehen wir in Deutschland? Übersicht der Literatur und Ergebnisse einer nationalen Umfrage
Authors: Oldhafer Felix , Beetz Oliver , Cammann Sebastian , Richter Nicolas , Klempnauer Juergen , Vondran Florian W. R.
Published: March 2021

Die Maschinenperfusion von Spenderlebern gilt als die aktuell wichtigste Neuerung in der Transplantationschirurgie, um dem anhaltenden Organmangel in der Lebertransplantation begegnen zu können. Die hypotherme Maschinenperfusion (HMP) ist sicher anzuwenden und scheint auch nach einer vorangegangenen kalten Ischämiephase bei Spendern mit einem Herzstillstand das Risiko für Gallenwegskomplikationen zur verringern sowie das Langzeitüberleben der Empfänger zu verbessern. Ein potenzieller Funktionstest der Spenderorgane während der HMP über die Bestimmung von Flavinmononukleotid befindet sich jedoch derzeit noch in klinischer Erprobung. Die normotherme Maschinenperfusion (NMP) hat ein höheres Risiko für technische Probleme, jedoch ermöglicht die Funktionstestung anhand konventioneller Laborparameter während der NMP eine deutliche Erweiterung des Spenderpools, wenngleich aktuell keine prospektive randomisierte Studie einen Überlebensvorteil für transplantierte Organe nach NMP aufzeigen konnte. Darüber hinaus lässt sich die Konservierungszeit der Spenderorgane mithilfe der NMP signifikant verlängern, was vor allem bei komplexen Empfängeroperationen und/oder aufwendiger Logistik vorteilhaft ist. Beide Methoden könnten für verschiedene Szenarien in der Transplantationsmedizin – theoretisch auch kombiniert – angewandt werden. Die Mehrheit der deutschen Transplantationszentren sieht in der Maschinenperfusion eine wichtige Innovation und führt bereits aktiv Perfusionen durch oder befindet sich in einer entsprechenden Vorbereitung hierauf. Die praktische Erfahrung in Deutschland ist insgesamt jedoch noch relativ gering: bei nur 2 Zentren, die mehr als 20 Perfusionen durchgeführt haben. In den kommenden Jahren sind daher multizentrische Anstrengungen zur Durchführung von klinischen Studien sowie der Erarbeitung von nationalen Leitlinien zur Maschinenperfusion unabdingbar, um das Potenzial dieser technologischen Entwicklungen fundiert definieren und für das Feld der Transplantationsmedizin optimal ausschöpfen zu können.
Avoidance of iodine deficiency/excess during pregnancy in Hashimoto’s thyroiditis
Authors: van Heek Lutz , Staudacher Christiane , Faust Michael , Chiapponi Costanza , Mettler Jasmin , Schmidt Matthias , Drzezga Alexander , Dietlein Markus , Kobe Carsten
Published: March 2021

Purpose Hashimoto’s thyroiditis is a common disease that also affects pregnant women. We analyzed to what extent the inflammatory process of Hashimoto’s thyroiditis changes with iodine prophylaxis in pregnant women. The target for immunologic activity was levels of thyroid antibodies (TPO).

Methods The data were collected retrospectively from 20 consecutive, pregnant patients who had been diagnosed with Hashimoto’s thyroiditis between 01.12.2012 and 01.12.2014 and had received iodine supplementation with 100 µg (n = 1) or 150 µg (n = 19). At least two measurements of TPO antibody levels taken during pregnancy and one after pregnancy were evaluated for each patient in the study group.

Results At the end of pregnancy, the average TPO antibody level for the 20 patients studied was 137 IU/ml (+/–214 IU/ml), the lowest being 16 IU/ml and the highest 1000 IU/ml. Despite iodine prophylaxis, levels of TPO antibodies decreased in 18 patients during pregnancy, falling below the reference value of 35 IU/ml in 5 cases. However, in one patient TPO antibodies increased from 60 IU/ml to 237 IU/ml during pregnancy while in another, levels remained constant at 1000 IU/ml.

Conclusion Iodine prophylaxis in pregnant women, taken at a dose of 100 or 150 μg daily was shown to have no negative systemic effects on Hashimoto’s thyroiditis in a group of pregnant women with increased TPO levels, and can therefore be recommended for expectant mothers, including those with this disease.
Hereditäre hämorrhagische Teleangiektasie: Symptome und diagnostische Latenz
Authors: Droege Freya , Kuerten Cornelius H. L. , Kaiser Christina , Dingemann Julia , Kaster Friederike , Dahlfrancis Philipp Marius , Lueb Carolin , Zioga Eleni , Thangavelu Kruthika , Lang Stephan , Geisthoff Urban
Published: March 2021

Hintergrund Patienten mit hereditärer hämorrhagischer Teleangiektasie (HHT) leiden unter einer systemischen Erkrankung des Gefäßbindegewebes, bei der eine Vielzahl verschiedener Symptome auftritt.

Material und Methoden Die Daten aller Patienten, die sich von April 2014 bis August 2019 im Westdeutschen Morbus-Osler-Zentrum vorstellten, wurden in einer retrospektiven Studie analysiert.

Ergebnisse Bei 235 Patienten konnte die Diagnose HHT als definitiv (235/282; 83 %) und bei 26 als möglich gestellt werden (26/282; 9 %). Die mittlere diagnostische Latenz zwischen Erstsymptomen und Diagnose betrug 18 Jahre. Direkte oder indirekte Blutungszeichen wurden oft als erste Symptome der Erkrankung HHT genannt (224/241; 93 %). 83 % der Patienten mit einem Grad der Behinderung gaben HHT als Hauptursache an. Insbesondere ältere, weibliche Patienten bzw. Patienten mit starker Epistaxis litten an einer chronischen Eisenmangelanämie (Eisensubstitution:148/261; 57 %; Erythrozytenkonzentrate: Mittelwert: 9 ± Standardabweichung: 41, Minimum – Maximum: 0–400, Anzahl der Patienten: 218). 10 % erhielten eine Thrombozytenaggregationshemmung oder Antikoagulation und tolerierten diese. 74 % der Patienten mit HHT pflegten ihre Nasenschleimhaut (177/238) und zeigten weniger Blutungen als Patienten ohne Nasenpflege (ESS: t-Test: 3,193; p = 0,003; Anämie: Chi-Quadrat: 5,173; p = 0,023).

Schlussfolgerungen Die Diagnoselatenz der Erkrankung HHT betrug knapp 2 Jahrzehnte. Patienten mit HHT leiden insbesondere an rezidivierenden Blutungen, die dabei meistindizierte Behandlung der ersten Wahl ist eine konsequente Nasenpflege und verschiedene koagulative Therapieoptionen. Bei Begleiterkrankungen mit Indikation zur Gerinnungshemmung lohnt es sich meist, deren Einsatz zu versuchen.
Collateral Formation from Left Lateral Thoracic Artery to the Adamkiewicz Artery
Authors: Fukui Toshihiro , Takaki Jun , Okamoto Ken
Published: March 2021

A 68-year-old man who had undergone descending thoracic aortic replacement was referred to our hospital with a thoracoabdominal aortic aneurysm. During the original surgery, the Adamkiewicz artery was directly reconstructed. However, multidetector row computed tomography showed occlusion of the reconstructed artery at its orifice, with supply by a collateral vessel from the left lateral thoracic artery. With careful incision to avoid damage to the collateral vessel, no postoperative neurological deficit was observed.
A Randomized, Double-Blind, Placebo-Controlled, Pilot Trial of Individualized Homeopathic Medicines for Cutaneous Warts
Authors: Dey Samit , Hashmi Shifa , Saha Sangita , Mandal Mahakas , Shaikh Abdur Rahaman , Agrawal Ekta , Ghosh Priyanka , Sehrawat Nisha , Koley Munmun , Saha Subhranil
Published: March 2021

Background Though frequently used in practice, research studies have shown inconclusive benefits of homeopathy in the treatment of warts. We aimed to assess the feasibility of a future definitive trial, with preliminary assessment of differences between effects of individualized homeopathic (IH) medicines and placebos in treatment of cutaneous warts.

Methods A double-blind, randomized, placebo-controlled trial (n = 60) was conducted at the dermatology outpatient department of D.N. De Homoeopathic Medical College and Hospital, West Bengal. Patients were randomized to receive either IH (n = 30) or identical-looking placebo (n = 30). Primary outcome measures were numbers and sizes of the warts; secondary outcome was the Dermatology Life Quality Index (DLQI) questionnaire measured at baseline, and every month up to 3 months. Group differences and effect sizes were calculated on the intention-to-treat sample.

Results Attrition rate was 11.6% (IH, 3; placebo, 4). Intra-group changes were significantly greater (all p < 0.05, Friedman tests) in IH than placebo. Inter-group differences were statistically non-significant (all p > 0.05, Mann-Whitney U tests) with small effect sizes—both in the primary outcomes (number of warts after 3 months: IH median [inter-quartile range; IQR] 1 [1, 3] vs. placebo 1 [1, 2]; p = 0.741; size of warts after 3 months: IH 5.6 mm [2.6, 40.2] vs. placebo 6.3 [0.8, 16.7]; p = 0.515) and in the secondary outcomes (DLQI total after 3 months: IH 4.5 [2, 6.2] vs. placebo 4.5 [2.5, 8]; p = 0.935). Thuja occidentalis (28.3%), Natrum muriaticum (10%) and Sulphur (8.3%) were the most frequently prescribed medicines. No harms, homeopathic aggravations, or serious adverse events were reported.

Conclusion As regards efficacy, the preliminary study was inconclusive, with a statistically non-significant direction of effect favoring homeopathy. The trial succeeded in showing that an adequately powered definitive trial is both feasible and warranted.

Trial Registration CTRI/2019/10/021659; UTN: U1111–1241–7340
Epidemiological Profile of Patients with Colorectal Cancer from a Hospital in Rio Grande do Sul, Brazil
Authors: Rohenkohl Cecilia Albertoni , Pastorello Julia , Costa Natália Rodrigues , Zabot Gilmara Pandolfo , Cassol Ornella Sari
Published: March 2021

Objective The present study describes the epidemiological profile of patients with colorectal cancer (CRC) from the Hospital de Clínicas de Passo Fundo, Passo Fundo, RS, Brazil, between January 1, 2007 and December 31, 2016.

Method Retrospective analysis of secondary data of 1,001 patients from the Hospital Cancer Registry.

Results Most subjects were Caucasian males, with a mean age of 63.68 years old. The majority of patients had incomplete elementary education and were married. In addition, 44.5% of the patients had a family history of cancer. Most subjects with a positive past or current history of alcohol intake or smoking were male. The diagnosis was mostly based on anatomopathological findings, with a predominance of adenocarcinomas and upper rectum and distal colon localization. Most lesions were in advanced stages, and the liver was the most common site for metastasis. The predominant treatment was surgery with neoadjuvant/adjuvant therapy. After the first treatment, 49.0% of the patients reported complete remission. The survival rate was 78.8% in 10 months.

Conclusion The present research analyzed the profile of CRC patients.
Evaluation of an Enteral Clonidine Taper following Prolonged Dexmedetomidine Exposure in Critically Ill Children
Authors: Crabtree Mara F. , Sargel Cheryl L. , Cloyd Colleen P. , Tobias Joseph D. , Abdel-Rasoul Mahmoud , Thompson R Zachary
Published: March 2021

The aim of the current study is to evaluate the use of an enteral clonidine transition for the prevention or management of dexmedetomidine withdrawal symptoms in critically ill children not exposed to other continuous infusion sedative agents. A retrospective, single-center study was conducted in patients ≤ 18 years of age admitted to the pediatric intensive care unit who received a continuous infusion of dexmedetomidine for ≥ 24 hours and who were prescribed enteral clonidine within 72 hours of dexmedetomidine discontinuation. Predefined withdrawal terminology was established to assess for hypertension, tachycardia, agitation, tremors, and decreased sleep. A total of 105 patients were included and received enteral clonidine for prevention or management of dexmedetomidine withdrawal symptoms, with 13 patients (12.4%) requiring a taper modification to manage withdrawal symptoms. The median duration of dexmedetomidine infusion was 120.5 hours (95.5, 143.5) and median peak infusion rate was 1 µg/kg/h (1, 1.2). A higher cumulative dexmedetomidine dose of 119.2 µg/kg (96.6, 154.9) and duration of 142.9 hours (122.6, 158.3) were noted in patients who required a taper modification. Risk factors for dexmedetomidine withdrawal such as dexmedetomidine duration and cumulative dose may help predict patients at the highest risk of withdrawal that would benefit from an enteral clonidine taper to prevent dexmedetomidine withdrawal symptoms. An enteral clonidine taper can be effective in the prevention and management of dexmedetomidine withdrawal symptoms.