bluuebunny/crossref_metadata_2025 huggingface dataset:
Advance on the preparation, physiological function and nanocarriers of resveratrol
Authors: Li Lingyi
Published: January 2021

Resveratrol is a natural compound that has many beneficial physiological functions. In recent years, the research on resveratrol has gradually become a hotspot. This article summarized the literature reports all over the world, classified and concluded the extraction technology, function and nano-delivery carriers of resveratrol. Solvent extraction, microwave-and ultrasonic-assisted extraction, supercritical carbon dioxide extraction and enzymatic hydrolysis method were respectively discussed in detail. Then the antioxidant property, antibacterial activity, antiumor effect and the prevention of cardiovascular disease of resveratrol were also discussed. Finally, the resveratrol-loaded nanocarriers, such as nanoparticles, nanoemulsions, solid lipid particles and nanosuspensions were summarized. And the future research direction of resveratrol were prospected, in order to provide references and orientations for the further development and research of resveratrol.
Research on the development status of domestic Korean catering industry
Authors: feng An , Haibo Zhao
Published: January 2021

With the steady development of China’s economy, the continuous improvement of people’s living standards, the transformation of people’s consumption concepts and the enhancement of their ability to accept foreign cultures, the special cuisine has been welcomed by Chinese people and became popular on their tables. Korean catering, which has its own unique flavor, is gradually developing among Chinese major cities. Compared with other regions, Wuhan, a second-tier city in China with relatively developed economy, relatively concentrated population, strong business culture and large proportion of young people, has a huge potential in food consumption. In addition, the unique conditions of Wuhan people’s positive attitude to foreign culture and the mature international metropolis culture of Wuhan itself all provide the sustainable development of Korean catering industry. This paper mainly analyzes the first-hand field research information and data of Korean catering industry status in Wuhan Optics Valley area rigorously and pragmatically to find and solve problems, as well as provide feasible strategies for college students in Korean catering business.
Research Progress on Physical Storage Methods of Toona Sinensis
Authors: Song Li , Benjiao Li , Binrong Ma , Yong Jing , Qiang Wang , Zheming Zhang
Published: January 2021

The toona sinensis (or Chinese toon) in rich in nutrition, with unique aroma and broad prospects for use. However, the toona sinensis is prone to respiration after being harvested. As a heat-sensitive vegetable, it is easy to lose water and decay. This paper introduced the latest research progress on physical preservation of toona sinensis before and during storage, providing references for developing new technologies of keeping Chinese toon fresh.
Study on the breaking process of jointed rock mass by disc cutters based on digital image correlation and infrared thermography
Authors: Junning Xie , Bolong Liu , Nianchang Zeng
Published: January 2021

Jointed rock masses are frequently encountered during the TBM excavation. To investigate the rock breakage mechanism of jointed rock mass by disc cutter and precursory information before rock failure, a series of indentation tests were performed on shear rheological test system. During the test, breaking process of specimens were recorded by digital image correlation system and thermal infrared imager simultaneously. Therefore, the strain fields and thermal infrared images of jointed rock mass by disc cutters were obtain. The experimental results show that the failure process of jointed rock mass can be divided into four stages: compaction stage, linear elastic stage, residual failure transition stage and post-failure stage. Besides, the characteristic of strain fields shows a good accordance with that of infrared radiation temperature fields at each stage. The failure of rock samples is dominated by shear failure, and the localized temperature rise is an important infrared precursor of rock fracture and instability. The experimental results are of great significance to the deep understanding of the breaking mechanism of jointed rock mass and warnings of engineering disasters.
Research on Settlement and Deformation Control of Newly-built High-speed Railway and Existing Line Foundation under Different Overlap and Filling Types
Authors: Li Wen-yi , Jin Chao-qi , Zhu Jun-hua , Guo Hao-sen , Luo Wen-jun , Chen Li
Published: January 2021

Subgrade filling of high-speed railway will cause additional settlement and deformation of existing lines.In this paper,using the finite element analysis platform (Taxis 2D) and considering the settlement of the existing line itself, This paper analyzes the impact of the new and old subgrade lap type and the layer filled this lesson of the new subgrade on the implementation of the existing subgrade. The results illustrate the following points:(1) Compared with different overlapping surface types, different filling those points have a greater impact on the settlement of the existing line; (2) The height of the steps is 0.6m and the width is 1.0m.In the subsequent layered filling construction process, each level The loading capacity of 30cm is more reasonable, which can effectively control the influence of the existing line on the additional settlement of the existing railway. The research results can provide a reference for the optimization of similar roadbed width construction.
Dynamic response of full-length bonded anchor cable in rock slope
Authors: Yong Nie , Yufei Zhao , Guangjin Du
Published: January 2021

The research on the anchoring mechanism of slope anchor cable under earthquake action is not in-depth. Therefore, it has become an urgent problem in engineering practice to study the seismic characteristics of slope anchoring system and then realize the optimal design of slope anchoring. In this paper, the dynamic response of a rock slope strengthened with a full-length bonded anchor cable is studied by centrifuge model test. It is found that the internal structure of the rock slope has an important effect on the length of the bonded anchor cable. The structural surface will lead to an increase of the effective anchorage length, and the stress concentration of anchor cable will occur at the structural surface. This provides some references for the optimization of traditional anchorage theory.
Research on the slope support technology in civil engineering construction
Authors: Lina Liu , Wei Han
Published: January 2021

For the whole process of civil engineering construction, slope support technology is a very key technical point of civil construction. Engineering and technical personnel shall be able to fully ensure the safety and firmness of the foundation structure of the engineering slope by setting up retaining walls or using other slope support treatment techniques, and extend the safe service life of civil engineering. Under this premise, engineering and technical personnel must integrate the technical measures of slope support into the construction process of civil engineering.
Research on evaluation method of bearing capacity of existing bridge based on static load test
Authors: Yang Qingcheng , Ning Yufeng , Sun Weiwei , Cheng Shunchao
Published: January 2021

The author carried out static load test research on a prestressed concrete rigid frame bridge. Under the action of static load, the most unfavorable section JM3 on the beam body was measured. The stress and deflection values at each measuring point were measured. The results show that the check coefficient of stress and deflection at each measuring point of the box girder does not exceed the standard limit value 1, the relative residual strain or deformation at each measuring point does not exceed the standard limit value 20%, and the overall bearing capacity of the bridge structure meets the normal use requirements of the design load (highway-I class).
Research and Application of Stress and Strain Testing Method for Plain Concrete Pile
Authors: Zhu Qinghua , Zuo Weilong , Xu Peng , Wang Hongyu
Published: January 2021

At present, the stress-strain test of pile body mainly focuses on precast pile and cast-in-place pile with reinforcement, and this is mainly because the pre-assembly of test components can be carried out in the pile body or reinforcement cage before the prefabricated pile is formed. When the pile is formed, it could be embedded together with the pile body or reinforcement cage. But for the cast-in-place plain concrete pile field test research report is rare. In view of the shortcomings of the existing test methods in the test of plain concrete piles, the resistance strain gauge and inclinometer are improved to realize their application in the field test of plain concrete piles, which is employed for the deformation characteristics test of plain concrete pile under horizontal load. The test results show the applicability of the improved test method, which provides useful references for similar research.
Selection and application of the minimum gas injection volume of air drilling with raise boring machine
Authors: HAN Bo , CHENG Shou-ye , NIU Hao , ZHAO Ming
Published: January 2021

Gas injection volume is the key parameter of air drilling with raise boring machine, and the determination of the minimum gas injection volume is one of the key technologies to improve the drilling speed and shorten the drilling period. Based on the characteristics of raise boring technology, the construction technique of raise boring with air as circulating medium is studied, and the double-channel structural characteristics of direct circulation system are discussed. On the basis of summarizing and analyzing the principle and characteristics of the calculation methods, the minimum gas injection volume required for rock carrying in the engineering of air drilling with raise boring machine is calculated by using the minimum velocity method. The research results provide a basis for the design of drilling parameters and are of great significance for expanding the application range of raise boring method and realizing the safe and rapid construction of shaft.
Research on the evaluation method of bearing capacity of existing Bridges based on dynamic load test
Authors: Yang Qingcheng , Ning Yufeng , Sun Weiwei , Cheng Shunchao
Published: January 2021

The author carried out dynamic load test research on a prestressed concrete rigid frame bridge. Under dynamic load, the ratios of the measured and theoretical frequencies of the first four vertical vibrations of the bridge were 1.081, 1.153 respectively. The corresponding measured damping ratios are 0.011, 0.010 respectively. The maximum dynamic coefficient of bridge sports car test is 1.049, and the corresponding dynamic strain increment coefficient is 0.059. The measured impact coefficient is between 0.012 and 0.049, which is basically equivalent to the design impact coefficient of 0.05.The test results show that the existing bridge works well under the test load, and the bearing capacity of the structure meets the requirements of the design load level.
Research on the Mechanical Characteristics of H-section Steel Frame under the Action of Thermo Mechanical Coupling
Authors: LI Yucheng , WANG Wei , WANG Xing
Published: January 2021

The research on the mechanical characteristics of concrete-filled steel tubular composite frame under high temperature fire environment is one of the research hotspots. In this paper, the finite element simulation software is used to analyze the concrete-filled steel tubular composite frame structure. The failure mode of the flexural deformation of the composite frame structure under high temperature fire environment is introduced. The simulation results of the deformation and displacement of the single-layer single span and two-layer two-span composite frame structure are deeply studied, including the different temperature field, structural field, structural field of each beam and column The results show that: with the temperature rising, the horizontal plastic strain, vertical displacement and local plastic region of beam and column are redistributed and changed in high temperature fire environment, and the flexural effect of two-story two-span concrete-filled steel tubular composite frame under different fire positions is analyzed. The results show that: with the temperature rising, the horizontal plastic strain at the concentrated load is not the results show that the deflection and deformation redistribution are obvious, and the deflection and deformation redistribution are obvious at the joint points of beams and columns. Finally, a mechanism is formed and destroyed. The flexure effect of mode 1 is larger than that of condition 2, which indicates that the flexural effect of two-story two span CFST composite frame under full cross-section fire is larger than that of condition 2 It should be better. The research results can provide reference value for the reinforcement and repair of CFST composite frame under high temperature fire.
Stability analysis of single-layer special-shaped folded-plane latticed shell
Authors: Li Jiajun , Yang Jing , Li Yunan , Yang Jian
Published: January 2021

Single-layer special-shaped folded-plane latticed shell had been applied in Shenyang culture and art center. In order to analysis its static stability, explore the form of buckling modes and find out its critical load factor, this paper analysis the optimized structure with MIDAS Gen. Eigenvalue buckling analysis and nonlinear buckling analysis showed that the in-plane stiffness of the structure is very large, and the out-plane stiffness is small, the upside structure is prone to instability. The critical load factor for this structure is 10.32, the structural overall stability is fine according to the code. This structures is sensitive to the initial geometric imperfections which could lower structural stability of the system.
Exchange Mechanism of the Suspended Sediment at the Mouth of Hangzhou Bay under Coastline Changes
Authors: Yu Zhuzhu , He Zhiguo , Li Li , Ye Taoyan , Xia Yuezhang
Published: January 2021

Based on FVCOM hydrodynamic numerical model and coastline topographic data in 2013, a three-dimensional numerical model of fine sediment transport in Hangzhou Bay has been established to explore the water and sediment exchange mechanism between Hangzhou Bay and the open sea at different typical sections. The results of validation with measured and satellite retrieved data show that the model can well simulate the process of water and sediment movement in Hangzhou Bay. Compared with the calculation results of the coastline topographic data of Hangzhou Bay in 1974 and 2020, the influence mechanism of shoreline change on the water and sediment exchange mechanism between Hangzhou Bay and the open sea has been studied. The results show that the sediment transport inside and outside the Hangzhou Bay is generally in the pattern of north-inflow and south-discharge. Compared with the coastline in 1974, the sediment transport from Yangshan port in the north of Hangzhou Bay and Zhoushan Islands in the middle of Hangzhou Bay increases when the coastline is pushed into the bay in 2020, while the outward sediment transport from Jintang Channel in the South decreases. The overall trend features that the sediment transport into the bay increases, with the bay mouth silting. In the three sections extending from Hangzhou Bay to the open sea, the inflowing water and sediment of the horizontal section on the north side is decreasing, while the discharged sediment from the south side and the inflowing water and discharged sediment from the vertical section at the east side are increasing.
Comparison and analysis of calculation of Bridge backwater based on Mike21 hydrodynamic model
Authors: Liu Jiang Chuan , Hu Zhu Qiu , Zhu Mao Yuan
Published: January 2021

The construction of bridges and other structures across the river will affect the flood discharge capacity and local water potential of the river.Based on navier-Stokes equation of MIKE21FM hydrodynamic module, this paper carries out two-dimensional numerical simulation of part of Shixi River. By optimizing the grid near the piers to reduce the difference brought by the terrain generalized grid of the real river, it simulates and analyzes the length of the curve of yong-high and Yong-water under different flood frequencies,the Nash-Sutcliffe efficiency coefficient and relative error analysis are used to verify the rationality of the results. The simulation results can accurately reflect the real changes of river water level, It provides a theoretical basis for flood impact analysis.
A Review on the Progress of Ecological Environment Research and Improvement of the Yellow River Basin
Authors: Tianchen Yu
Published: January 2021

Ecological protection and high-quality development in the Yellow River Basin is a major national strategy for regional economic growth and embodiment of green and coordinated policies. This paper expounds the research direction, implementation measures and existing achievements in the ecological theme for the Yellow River basin in China. It also introduces the methods to realize ecological optimization from the perspective of water resources, which is of certain significance for the further development of ecological protection and rational utilization of water resources in the basin.
Design and evaluation of a quasi-zero-stiffness isolator using flexibly supported negative stiffness mechanism
Authors: Lou Yu , Zhou Peng
Published: January 2021

In traditional quasi-zero-stiffness (QZS) isolation system, the negative stiffness part is usually fixed rigidly, lacking of effective amplifying mechanism. For reaching a quasi-zero state, the value of negative stiffness need to be very large to offset the positive stiffness of the structure. This paper proposes a novel isolator incorporating a flexible support to magnify negative stiffness part for effective realization of quasi-zero state. First, the concept and formulation of the innovative quasi-zero isolator are presented. Equivalent model for the flexibly supported negative stiffness part is established, followed by a parametric analysis to reveal the amplification effect. Thereafter, a design method is developed and numerical simulation is performed to verify the isolating performance. The results show that a flexible support enlarges the negative stiffness remarkably, thereby resulting in a cost-effective design. The optimized QZS isolator is capable of isolating external disturbance significantly.
Study on electromagnetic environment analysis and lightning protection in buildings
Authors: Ye Gen , Lu Yufa , Yang Guirong , Chen Weichao
Published: January 2021

When a direct strike occurs, the lightning surge current will intrude into the steel frame and steel bar of the building, forming a high lightning electromagnetic environment inside the building, which will affect the telecommunications equipment set in the building. Therefore, the problem of lightning protection in buildings becomes more and more important. In this paper, by studying the distribution law of lightning electromagnetic field in buildings, the intensity of magnetic field generated in buildings under different lightning strikes is analyzed. According to the three-dimensional diagram and equivalent diagram of the intensity of lightning magnetic field in each case, when the building encounters direct lightning, the lightning electromagnetic field is the strongest near the leadoff line, and the middle zone is weak. The lightning protection measures inside the building are put forward.
Study on the relationship between the restorative effect of urban green space and personal environmental preference ——A case study of the Longtan park in Taiyuan
Authors: Zhihao Xia
Published: January 2021

To improve the design strategy of urban green space and enhance the restorative effect of urban green space, this study took the Longtan Park in Taiyuan city as an example to test the relationship between the restorative effect and personal environmental preference based on eight perceived sensory dimensions in green space and restoration environment scale-Chinese version. The survey was conducted by questionnaire and interview. The results show that there is a positive correlation between the restorative effect of environment and personal environmental preference, while personal environmental preference is related to age characteristics. Children prefer rich in species and nature. The young prefer serene and refuge. Middle-aged people prefer nature and serene. Elderly people prefer social and prospect.
Fault identification for chiller sensor based on partial least square method
Authors: Wu Bang , Hu Yunpeng , Zhou Chuanhui , Chen Guaiguai , Li Guannan
Published: January 2021

Sensor failures can lead to an imbalance in heating, ventilation and air conditioning (HVAC) control systems and increase energy consumption. The partial least squares algorithm is a multivariate statistical method, compared with the principal component analysis, its compression factor score contains more original data characteristic information, therefore, partial least squares have greater potential for fault diagnosis than the principal component analysis. However, there are few studies based on partial least squares in the field of HVAC. In order to introduce partial least squares into the field, based on the partial least squares fault detection theory, a fault analysis method suitable for this field is proposed, and the RP1403 data published by ASHARE was used to verify this method. The results show that on the basis of selecting the appropriate number of principal components, partial least squares have the ability to diagnose the fault of the chiller sensor. With the known fault source, partial least squares regression, a method with better data reconstruction accuracy than principal component analysis, is used to repair the fault. Finally, the purpose of fault identification can be achieved.
Research on Quality Risk Assessment and Application of Large-scale Clusters of Engineering Project
Authors: Chen Shan , Liang Xiaoguang , Li Mingmao , Zou Chuanlong
Published: January 2021

In order to study the quality risk of large-scale clusters of engineering project and makes the characteristic analysis of large-scale clusters of engineering project and evaluates quality risk, the author uses analytic hierarchy process to quantify quality risk factor, and the following conclusions are obtained: (a) Construction management unit that makes the project decision-making mainly controls the QRM, comparatively speaking, it has little control over quality risk when the project is completed and ready to get acceptance (b) In the project decision-making stage, the Construction Technology has the greatest influence on the project quality management. This paper puts forward the suggestion that the influence of quality risk factors should be quantified by associated experts, so as to provide a reference for the construction quality management of large-scale cluster projects.
A Review of the Research on the Influence of Cavitation and Abrasion on Hydroturbine Performance
Authors: Tianchen Yu
Published: January 2021

Large and medium sized water conservancy projects generally have comprehensive benefits such as flood control, water supply, irrigation and power generation. As the main hydraulic power generation equipment, the safe and economic operation of hydroturbine generator sets is of vital importance. For a hydroturbine affected by the flow of water in the running process, the paper explores the cavitation and abrasion phenomena, analyses the phenomenon of resource waste, energy waste and material waste caused by unreasonable protection of water turbine, and introduces relevant protective measures. These results further enhance the understanding of the corrosion resistance of the hydroturbine and could be used to optimize the hydroturbine protection techniques.
Operation status and line optimization of Wanda Plaza Parking lot
Authors: Meng Zhe , Guo Baohua , Wang Huihui , Guo Qingwen , Zhu YeLan
Published: January 2021

Vehicle parking is not only an important problem in urban traffic, but also an important factor affecting the relationship between cities and within cities. In this paper, by investigating the parking conditions of Jiaozuo Wanda Plaza in 2018, important parameters such as average parking time on weekdays and holidays, berth turnover rate, parking utilization rate and centralized parking index were obtained. Based on the obtained parameters, multi-angle optimization analysis was conducted on the parking lot. In order to reduce the congestion of the entrance and exit of parking lots and improve parking efficiency, this paper adopts the method of increasing the entrance and exit of parking lots and optimizing the route. It has great reference value in practical application.
Tracking Control of Intelligent Vehicle Lane Change Based on RLMPC
Authors: Hou Quanshan , Zhang Yanan , Zhao Shuai , Hu Yunhao , Shen Yongwang
Published: January 2021

Autonomous lane changing, as a key module to realize high-level automatic driving, has important practical significance for improving the driving safety, comfort and commuting efficiency of vehicles. Traditional controllers have disadvantages such as weak scene adaptability and difficulty in balancing multi-objective optimization. In this paper, combined with the excellent self-learning ability of reinforcement learning, an interactive model predictive control algorithm is designed to realize the tracking control of the lane change trajectory. At the same time, two typical scenarios are verified by PreScan and Simulink, and the results show that the control algorithm can significantly improve the tracking accuracy and stability of the lane change trajectory.
Application of the Concept of Presentational Understanding in the Practice Courseware of Electric Power Maintenance
Authors: Ma Wenquan , Qin Hongwei , You Yi , Ding Huaxiao
Published: January 2021

Currently, the level of intelligent construction in the power industry is constantly improving, and power maintenance has gradually realized intelligent control and management, which greatly guarantees the operational safety of smart grids. In order to solve the problem that traditional courseware cannot meet the practical requirements of electric power maintenance, a kind of practical electric power maintenance courseware is researched and designed based on the concept of presentational understanding. From the perspective of improving the real-time and accuracy of power overhaul, the monitoring information of the substation is effectively presented. On this basis, effective inspection and repair work are carried out on the secondary circuit of the substation. The content of the courseware enhances the deeper understanding of the electric power maintenance staff.
Quantification of defects in an aluminum plate using direction-tunable shear horizontal wave imaging
Authors: Ahmad Mubarak , Liu Zenghua , Basit Abdul , Jiang Wenshuo , Bin Wu , He Cunfu
Published: January 2021

The quantification of damage, in plates, pipes and such like structures, is one of the current research areas. In this study, to estimate the notch size, shape, and orientation was carried out experimentally based on fundamental shear horizontal mode, SH0 mode. Using least number of transmitters, the reconstruction algorithm for the probabilistic inspection of damage (RAPID) has been used to carry out fast and efficient investigation of scattered waves using SH0wave interaction with notch at various incident angles. An approach of ultrasonic guided waves and (RAPID) algorithm, using a direction-tunable shear-horizontal mode array magnetostrictive patch transducer (DT-SHMA-MPT), the notch in a thin aluminum plate is experimented. Firstly, the RAPID algorithm, based on SH0mode, is used here to quantitatively study a notch in a thin aluminium plate. Secondly, the imaging application using DT-SHMA-MPT is achieved. Experiments were conducted using an array of eight DT-SHMA-MPTs based on a pitch-catch mode to utilize the scattered waves at the notch. The results obtained through experiments reveal the effect of directionality of the scattered waves and have find out the optimal transducers configuration. The localization, quantification and orientation at the same time are obtained using only two or three transmitters. To improve the accuracy of imaging, a threshold value was selected. The presented approach can be used to detect, locate and image the surface defects in aluminum plate.
Noise characteristic analysis and sound sources identification for rod–airfoil interaction using different subgrid-scale models
Authors: Yang Chenghao , Feng Heying , Peng Yehui
Published: January 2021

Four subgrid-scale models based on large eddy simulation (LES), such as Smagorinsky–Lilly (SL), dynamic Smagorinsky–Lilly (DSL), wall-adapting local eddy-viscosity (WALE), and dynamic kinetic-energy transport (KET) were used and couple Ffowcs Williams–Hawkings equation to accurately analyze and identify the characteristics and position of the sound sources of rod–airfoil interaction. The results of four models were compared with experimental data. It was found that the DSL model was the optimal subgrid-scale model for the study of the interaction noise considering the calculation accuracy. Therefore, the DSL model was selected for analyzing and identifying the characteristics and location of the interaction noise source. During the calculation, solid and permeable data surfaces were used for acoustic integral surfaces. The results show that the impact of the quadrupole source is negligible at a low Mach number, and the dipole noise coming from the pressure fluctuations is dominant. Meanwhile, the dipole noise from the airfoil is louder than that from the rod; the leading edge of about 30% chord length of airfoil the is the main sound source of interference effect. Above results can provide guidance for research of blade-vortex interaction noise.
The Effect of Fixing Method on the Result of Ultrasonic Infrared Thermography Testing
Authors: Tian Gan , Li Fazhong , Feng Shuaixing , Wan Haohao , Kou Guangjie
Published: January 2021

Considering the influence of the fixing method of the component in the system on its results in ultrasonic infrared thermography testing, the detection experiments of the cracked plat structure with fixing at one end and fixing at two ends are carried out through different fixing methods of the equivalent structure. The results show that for the same structure to be detected, the more the bounds are fixed, the more the degrees of freedom are restricted, the less ultrasonic energy is dissipated during the inspection process, and the better the inspection effect. The work has positive significance for the selection of detection parameters in ultrasonic infrared thermography testing, helpful to provide some references for it.
Smart bookcase based on image recognition
Authors: Liu Ziyang
Published: January 2021

With the improvement of people’s living standards, the demand for books and the efficiency and accuracy of accessing books are also increasing. Because the information displayed to readers on the library management system is the position of the book when it is neatly arranged, sometimes the position of the book is inconsistent with the actual position of the book, which increases the difficulty for readers to find the target book. The traditional bookcase has a simple structure, and it takes a certain amount of time to search for books on weekdays. In view of the time-consuming situation of borrowing books, and in order to make it convenient for borrowers to find books, it is extremely important to develop a new type of networkable smart bookcase for libraries.
Design of monitoring system for radioactivity and radiation dose in nuclear medicine
Authors: Yang Bin , Zhao Xiaowen , Wang Xinwei , Zhao Hongtao , Yan Haixia , li Yan , li Gang
Published: January 2021

In this paper, an intelligent radioactivity and radiation dose monitoring system is designed, which can be used in the field of nuclear medicine. The system can dynamically monitor the body surface radioactivity and radiation dose rate of patients receiving 131I radioactive drug treatment, and can identify the personnel who exceed the radiation threshold and send out sound and light alarm. Compared with other monitoring equipment, this system has higher accuracy and can guide the clinical treatment of nuclear medicine scientifically.
Regularity of the time constant for a supercritical Bernoulli percolation
Authors: Dembin Barbara
Published: January 2021

We consider an i.i.d. supercritical bond percolation on ℤd, every edge is open with a probability p > pc(d), where pc(d) denotes the critical parameter for this percolation. We know that there exists almost surely a unique infinite open cluster 𝒞p. We are interested in the regularity properties of the chemical distance for supercritical Bernoulli percolation. The chemical distance between two points x, y ∈ 𝒞p corresponds to the length of the shortest path in 𝒞p joining the two points. The chemical distance between 0 and nx grows asymptotically like nμp(x). We aim to study the regularity properties of the map p → μp in the supercritical regime. This may be seen as a special case of first passage percolation where the distribution of the passage time is Gp = pδ1 + (1 − p)δ∞, p > pc(d). It is already known that the map p → μp is continuous.
Preoperative Embolization Facilitates Segmental Resection of Pulmonary Sequestration in an Infant
Authors: Prasad Dilan , Pennell Christopher , Arthur Lindsay Grier , Prasad Rajeev
Published: January 2021

The most common congenital lung malformations are congenital pulmonary airway malformations and pulmonary sequestrations. Many surgeons advocate resection to prevent complications of infection, malignancy, and pneumothorax. The standard of care is lobectomy, but segmentectomy and embolization alone have been reported. These methods avoid the complications of lobectomy but are not widely practiced due to concerns about incomplete resection or involution of the lesion. We present a novel approach to the treatment of a pulmonary sequestration in a 7-month-old male using preoperative embolization followed by a sublobar pulmonary resection. The embolization clearly demarcated the affected lung intraoperatively, thereby facilitating complete removal of the lesion with a segmental lung resection rather than complete lobectomy.
Advantage of Using 8K Ultra-High-Definition Television System for Kasai Portoenterostomy for Biliary Atresia
Authors: Miyagi Hisayuki , Ishii Daisuke , Hirasawa Masatoshi , Shonaka Tatsuya , Sumi Yasuo , Azuma Nobuyoshi
Published: January 2021

Kasai portoenterostomy (KPE) is currently the first-line treatment for biliary atresia. Many pediatric surgeons have reported that the dissection of the fibrous remnant at the porta hepatis is one of the most important components of this procedure. Furthermore, laparoscopic portoenterostomy is being increasingly used to treat biliary atresia.

An advantage of laparoscopic surgery is that surgeons can more easily identify microbiliary ducts, owing to the magnification. We report the case of a 61-day-old girl on whom we performed an exploratory laparotomy and diagnosed type III biliary atresia using intraoperative cholangiography. For the first time, we performed an open KPE using an 8K ultra-high-definition television system. This allowed us to clearly view the porta hepatis and to successfully perform the portoenterostomy.
Faber–Krahn inequalities for Schrödinger operators with point and with Coulomb interactions
Authors: Lotoreichik Vladimir , Michelangeli Alessandro
Published: January 2021

We obtain new Faber–Krahn-type inequalities for certain perturbations of the Dirichlet Laplacian on a bounded domain. First, we establish a two- and three-dimensional Faber–Krahn inequality for the Schrödinger operator with point interaction: the optimizer is the ball with the point interaction supported at its center. Next, we establish three-dimensional Faber–Krahn inequalities for a one- and two-body Schrödinger operator with attractive Coulomb interactions, the optimizer being given in terms of Coulomb attraction at the center of the ball. The proofs of such results are based on symmetric decreasing rearrangement and Steiner rearrangement techniques; in the first model, a careful analysis of certain monotonicity properties of the lowest eigenvalue is also needed.
Analysis of wireless power transmission system with negative impedance converter
Authors: Jian Lei , Wang Junshan , Li Huafeng , Zhu Jing , Ding Qingjun
Published: January 2021

In this study, we analyze a resonant coupled wireless power transmission system with a negative impedance converter (NIC). The expressions for the output power of this system are obtained. The constraints of system parameter selection are determined according to the practical limitations of the NIC. The energy efficiency ratio (EER) is introduced to represent the relationship between the increase in system output power and the additional loss caused by the introduction of the NIC. The influence of the NIC on the EER was tested by changing the negative resistance. The experimental results show that the NIC reduces the loop impedance, increases the loop current, and improves the output power of the system. In addition, setting the appropriate parameters of the NIC can effectively increase the EER of resonant coupled radio power transmission by more than 4%.
Shock focusing effects on silica phase production during cyclotrimethylene trinitramine/2,4,6-trinitrotoluene detonations
Authors: Langenderfer Martin , Fahrenholtz William G. , Heniff Jeffrey , Nguyen Lily , Watts Jeremy , Johnson Catherine E.
Published: January 2021

Detonation is an increasingly studied method for the synthesis of nanomaterials due to the rapid reaction rate producing extreme pressures and temperatures for short durations, which can result in the production of ultra-hard and high-temperature nanomaterials. The present study shows that phase formation in detonation depends on the distribution of inert additives in the explosive charge. Numerical simulations and experimental validation were conducted on silica powders that were shock loaded by detonation of a 3.8 cm diameter cylindrical explosive charge composed of cyclotrimethylene trinitramine, 2,4,6-trinitrotoluene, and paraffin wax. Silica was incorporated into the explosive in three configurations and at two different starting particle sizes in both simulation and experiments. The detonation residues were purified to concentrate the silica and characterized via x-ray diffraction with Rietveld refinement and optical microscopy. Loading conditions and silica phase morphology were not consistent between the configurations and starting size of silica incorporated into the charge. The implication of these results is that the prediction of phase production in detonation synthesis experiments cannot be based on Chapman–Jouguet steady detonation parameters of the explosive matrix but must also include analysis of shock interaction and heat transfer into the additives incorporated into the explosive.
Polariton response in the presence of Brownian dissipation from molecular vibrations
Authors: Kansanen Kalle S. U. , Toppari J. Jussi , Heikkilä Tero T.
Published: January 2021

We study the elastic response of a stationarily driven system of a cavity field strongly coupled with molecular excitons, taking into account the main dissipation channels due to the finite cavity linewidth and molecular vibrations. We show that the frequently used coupled oscillator model fails in describing this response especially due to the non-Lorentzian dissipation of the molecules to their vibrations. Signatures of this failure are the temperature dependent minimum point of the polariton peak splitting, the uneven polariton peak height at the minimum splitting, and the asymmetric shape of the polariton peaks even at the experimentally accessed “zero-detuning” point. Using a rather generic yet representative model of molecular vibrations, we predict the polariton response in various conditions, depending on the temperature, molecular Stokes shift and vibration frequencies, and the size of the Rabi splitting. Our results can be used as a sanity check of the experiments trying to “prove” results originating from strong coupling, such as vacuum-enhanced chemical reaction rate.
Observation of photon antibunching with only one standard single-photon detector
Authors: Liu Shaojie , Lin Xing , Liu Feng , Lei Hairui , Fang Wei , Jin Chaoyuan
Published: January 2021

The second-order photon correlation function g2(τ) is of great importance in quantum optics. g2(τ) is typically measured with the Hanbury Brown and Twiss (HBT) interferometer, which employs a pair of single-photon detectors and a dual-channel time acquisition module. Here, we demonstrate a new method to measure and extract g2(τ) with a standard single-photon avalanche photodiode (dead-time = 22 ns) and a single-channel time acquisition module. This is realized by shifting the coincidence counts of interest to a time window not affected by the dead-time and after-pulse of the detection system using a fiber-based delay line. The new scheme is verified by measuring g2(τ) from a single colloidal nanocrystal. Photon antibunching is unambiguously observed and agrees well with the result measured using the standard HBT setup. Our scheme simplifies the higher-order correlation technique and might be favored in cost-sensitive circumstances.
Modeling of the thermal migration mechanisms of atomic oxygen in Ar, Kr, and Xe crystals
Authors: Leibin Iosif V. , Kalinina Inna S. , Bezrukov Dmitry S. , Buchachenko Alexei A.
Published: January 2021

Accommodation and migration of the ground-state (2s22p4 3P) oxygen atom in the ideal Ar, Kr, and Xe rare gas crystals are investigated using the classical model. The model accounts for anisotropy of interaction between guest and host atoms, spin–orbit coupling, and lattice relaxation. Interstitial and substitutional accommodations are found to be the only thermodynamically stable sites for trapping atomic oxygen. Mixing of electronic states coupled to lattice distortions justifies that its long-range thermal migration follows the adiabatic ground-state potential energy surface. Search for the migration paths reveals a common direct mechanism for interstitial diffusion. Substitutional atoms are activated by the point lattice defects, whereas the direct guest–host exchange meets a higher activation barrier. These three low-energy migration mechanisms provide plausible interpretation for multiple migration activation thresholds observed in Kr and Xe free-standing crystals, confirmed by reasonable agreement between calculated and measured activation energies. An important effect of interaction anisotropy and a minor role of spin–orbit coupling are emphasized.
On-surface formation of metal–organic coordination networks with C⋯Ag⋯C and C=O⋯Ag interactions assisted by precursor self-assembly
Authors: Schultz Jeremy F. , Yang Bing , Jiang Nan
Published: January 2021

Surface-bound reactions are commonly employed to develop nanoarchitectures through bottom-up assembly. Precursor molecules are carefully designed, and surfaces are chosen with the intention to fabricate low-dimensional extended networks, which can include one-dimensional and two-dimensional structures. The inclusion of functional groups can offer the opportunity to utilize unique chemistry to further tune the bottom-up method or form novel nanostructures. Specifically, carbonyl groups open up new avenues for on-surface coordination chemistry. Here, the self-assembly and formation of an organometallic species via the thermally induced reaction of 3,6-dibromo-9,10-phenanthrenequinone (DBPQ) molecules were studied on Ag(100) and Ag(110). Low-temperature ultrahigh vacuum scanning tunneling microscopy revealed the room temperature formation of self-assemblies defined by hydrogen and halogen bonds on Ag(100). Following a thermal anneal to 300 °C, DBPQ on Ag(100) was found to form metal–organic coordination networks composed of a combination of organometallic species characteristics of Ullmann-like coupling reactions and carbonyl complexes. On Ag(110), the C–Br bonds were found to readily dissociate at room temperature, resulting in the formation of disordered organometallic species.
A model for dynamical solvent control of molecular junction electronic properties
Authors: Gelin Maxim F. , Kosov Daniel S.
Published: January 2021

Experimental measurements of electron transport properties of molecular junctions are often performed in solvents. Solvent–molecule coupling and physical properties of the solvent can be used as the external stimulus to control the electric current through a molecule. In this paper, we propose a model that includes dynamical effects of solvent–molecule interaction in non-equilibrium Green’s function calculations of the electric current. The solvent is considered as a macroscopic dipole moment that reorients stochastically and interacts with the electrons tunneling through the molecular junction. The Keldysh–Kadanoff–Baym equations for electronic Green’s functions are solved in the time domain with subsequent averaging over random realizations of rotational variables using the Furutsu–Novikov method for the exact closure of infinite hierarchy of stochastic correlation functions. The developed theory requires the use of wideband approximation as well as classical treatment of solvent degrees of freedom. The theory is applied to a model molecular junction. It is demonstrated that not only electrostatic interaction between molecular junction and solvent but also solvent viscosity can be used to control electrical properties of the junction. Alignment of the rotating dipole moment breaks the particle–hole symmetry of the transmission favoring either hole or electron transport channels depending upon the aligning potential.
Photopharmacological compounds based on azobenzenes and azoheteroarenes: principles of molecular design, molecular modelling, and synthesis
Authors: Ryazantsev Mikhail N. , Strashkov Daniil M. , Nikolaev Dmitrii M. , Shtyrov Andrey A. , Panov Maxim S.
Published: January 2021

Photopharmacology is a field of medicine and pharmacology that uses light to selectively activate or deactivate pharmaceutical agents. This approach significantly enhances and localizes the drug action and, therefore, reduces its side effects. Apart from the bioactive moiety, any photopharmacological compound should contain a photoactive group that must absorb light at the desired wavelength and reorganize the molecular structure after photoactivation. The design of an effective photopharmacological compound requires careful tuning of physical, chemical, and biological properties. The present review summarizes and analyzes the main approaches to the molecular design of photopharmacological drugs based on azobenzene or azoheteroarenes. The main ideas and methods used for tuning spectral and photochemical properties of compounds of this class are discussed. A comparative analysis of main computational methods for theirin silicoscreening is carried out; the most common approaches to the synthesis of azobenzenes and azoheteroarenes derivatives are systematized. Special attention is given to the methods and approaches that are specific to the molecular design of photopharmacological compounds with required physicochemical and photochemical properties.

The bibliography includes 212 references.