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This paper analyzed the pre-stressing mechanism of the steel wire and the damage process of the pipeline, and proposes a method of PCCP wire broken warning and alarm threshold assessment based on mechanical simulation analysis. The PCCP finite element model was established by ABAQUS program, and the complete construction process including laying bedding, installing pipelines, backfilling in steps was simulated, and the stress state of pipeline prestressing steel wires, steel cylinders and pipe core concrete was calculated under nearly 100 working conditions with different depths of burial and different design working pressures. It was proposed to take the maximum permissible number of broken wires of the pipe core concrete cracked under the action of water hammer as the early warning threshold for the bursting of the pipeline, and the maximum permissible number of broken wires in the limit state of the buried bearing capacity of the pipeline as the alarm threshold for pipe bursting, and analyzed the relationship between the PCCP wire broken warning and the alarm threshold under different working pressures and burial depths. [ABSTRACT FROM AUTHOR]

BACKGROUND: Distal radial fracture involving dorsal ulnar fragment type belongs to unstable fractures, AO classification of 23C type and the middle column fractures of three-column classification. If dorsal ulnar fragment cannot be effectively fixed, it will affect the stability of radial joints and ulnar radial joints. The fixation effect of dorsal volar plate alone on dorsal ulnar fragment is limited. Although the fixation effect of dorsal volar double plate is effective, it increases the trauma and treatment cost, which is not in line with the current Diagnosis Related Groups policy. The addition of dorsal Kirschner wire fixation may be a relatively feasible plan. OBJECTIVE: A finite element model of AO/ASIF 23-C1 distal radial fracture was established to compare the differences in biomechanical stability between volar locking plate and volar locking plate plus dorsal Kirschner wire, especially focusing on the fixation effect of dorsal ulnar fragment, providing a reference for clinical application. METHODS: Using reverse modeling technology, the CT data of healthy femur of a 42-year-old male and internal fixation data were imported into relevant software to establish three-dimensional finite element models of AO/ASIF 23-C1 distal radial fractures with volar locking plate and volar locking plate with dorsal Kirschner wire. The models were subjected to 100 N axial stress, or 1 Nm bending or torsional stress, respectively. The maximum displacement, maximum Von Mises stress and stress distribution of dorsal ulnar fragment were compared between the two groups. RESULTS AND CONCLUSION: (1) The stress on the internal fixation was 2-10 times that on the bone under the two fixation methods, which met the requirements of fracture fixation. (2) Under the three different loads, there was no significant difference between the two groups in the stress peaks of both bone and internal fixation (< 30%). Under an axial load, the peak stress on the internal fixation was 3-4 times that on the bone. However, under bending load, the peak stress of internal fixation was 8-10 times that of bone, while under torsion load, the peak stress of internal fixation was only twice that of bone. (3) Under an axial load, the maximum displacements of the dorsal ulnar fragment between the two groups were very small and the difference was small, only 0.056 mm and 0.047 mm, respectively, indicating good stability of the fragment. Under bending load, the maximum displacement of single plate group was 2.4 times that of Kirschner wire group. Under torsion load, the maximum displacement of the single plate group was 2.7 times that of the Kirschner wire group. (4) It is indicated that the volar locking plate with Kirschner wire can more effectively fix the dorsal ulnar fracture fragment, with more uniform stress distribution, improve the fixation strength, and does not significantly increase the treatment cost. It is more suitable for the treatment of distal radial fractures involving the dorsal ulnar fracture fragment under the current Diagnosis Related Groups policy. [ABSTRACT FROM AUTHOR]

A model for controlling the electrolytic phosphating process was established based on related theories. A general empirical formula for calculating the process condition i.e. electrical current for electrolytic phosphating during steel wire manufacturing with an independent power supply for single wire was derived and verified according to the actual production. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology & Material is the property of Automobile Technology & Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the surface quality and reduce the edge burrs, the effects of current, pulse width and pulse spacing on the machining effect of PtIr alloy WIM were studied. The results show that the machining parameters have an important effect on the surface roughness and edge burr of the material. The machining parameters of wire electrical discharge machining(WEDM) were optimized, the current was 5 A, the pulse width was 5 µs, the pulse distance was 5 µs, the machining speed was 150 steps/S, the diameter of molybdenum wire was 0.1 mm, the surface roughness Ra was 0.14 µm, and the cutting precision tolerance reached ±0.006 mm. [ABSTRACT FROM AUTHOR]

As a typical hard and brittle material, gallium oxide crystal (β-Ga2O3) is easy to crack during processing. Diamond wire saw is the main way to produce β-Ga2O3 wafers. During the slicing process, a microcrack damage layer will be generated on the surface of the wafer. Under the stress, the microcracks will expand, leading to material breakage and fracture. In this paper, a finite element model of diamond wire sawing of β-Ga2O3 (010) crystal surface was established. The distribution of mechanical stress, thermal stress, and thermal-mechanical coupling stress during the sawing process were studied. The effects of sawing wire speed, feed speed and different parameter combinations under constant speed ratio on the thermal-mechanical coupling stress were analyzed. The research results show that: the thermal stress generated by sawing heat dominates the thermal-mechanical coupling stress during the sawing process; the mechanical stress caused by sawing force has a small numerical value and proportion, but it affects the distribution of thermal-mechanical coupling stress; increasing sawing wire speed and feed speed will increase the thermal-mechanical coupling stress. [ABSTRACT FROM AUTHOR]

With the application of modern information technology as the essential feature, the virtual simulation experimental teaching occupies an important role in the new teaching system of higher education. In order to make students deeply involved in the experimental teaching of electronic packaging technology, this paper, taking gold-based wire bonding as an example, explains the necessity of virtual simulation experimental teaching. The goal of experimental teaching is to improve students' independent learning and exploration abilities and engineering practice innovation abilities. Based on the principle of "two-essences and one-degree", the experimental teaching contents with a integrated design and inquiry-type feature have been set up, thereby establishing a comprehensive "Trinity" teaching evaluation system. Virtual simulation experimental teaching breaks through the limitations of traditional experimental teaching, which enables students to independently design experimental content and explore scientific mechanisms. It also broadens the breadth and depth of experimental teaching, thus fundamentally enhancing the quality of experimental teaching in electronic packaging technology major. [ABSTRACT FROM AUTHOR]

BACKGROUND: During orthodontic treatment, the arch wire is an important part of the fixed appliance. The choice of arch wire largely determines the efficiency of tooth alignment. Among them, nickel-titanium alloys are widely used in fixed orthodontics due to their superelasticity and shape memory effect, and have become a research hotspot. OBJECTIVE: To review the development history and research progress of nickel titanium arch wires. METHODS: The literature search was performed in PubMed, Web of Science and CNKI databases. The Chinese and English keywords were “orthodontics, NiTi”. The articles were screened according to the inclusion and exclusion criteria. Finally, 77 articles were included for review. RESULTS AND CONCLUSION: Many scholars did researches to overcome the drawbacks of the NiTi arch wire, such as improving the composition, manufacturing process and surface modification. However, the current finished nickel-titanium arch wires still have various drawbacks, such as poor aesthetic properties of the arch wires; the release of nickel ions may cause allergic reactions, and the aesthetic coating is easy to fall off. Although there are commercial products of NiTi arch wire and are widely used in clinical orthodontic treatment, due to the complexity of orthodontic process, and many researchers are still in the laboratory stage; there is no ideal NiTi arch wire to meet the needs of all aspects of orthodontic clinical treatment. The improvement of various types of NiTi arch wire is an important supplement and development to the existing NiTi arch wire, and is expected to play a huge role in clinical applications in the future. [ABSTRACT FROM AUTHOR]

In order to improve the slicing quality of single crystal silicon wafers, a tension model for multi wire sawing of single crystal silicon ingots was first established, and the reliability of the axial force model of the spindle under the assistance of the material pendulum was verified by comparing theoretical data with experimental data. On the basis of these models, a spindle axial displacement experimental device was designed to explore the effect of bearing installation parameters on the spindle axial displacement. The experimental results show that the interference will change the stiffness of the bearing joint, and then affect the axial displacement of the spindle. The axial displacement increases with the increase of the interference fit of the angular contact ball bearing, and decreases with the increase of the interference fit of the cylindrical roller bearing. When the interference of angular contact ball bearings is 0.01 mm and the interference of cylindrical roller bearings is 0.03 mm, the minimum displacement is 1.61 μm. The experimental conclusion provides a theoretical basis for optimizing the installation process of the spindle of the multi diamond wire sawing and improving the surface quality. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Effective surgical fixation should be performed for patients with ulnar coronoid fractures with unstable elbow joint. When the coronoid fracture fragment is large, there are more internal fixation materials, such as microplates, steel wires, screws, and anchors. However, when the fracture fragment is small, choosing the appropriate internal fixation device is a difficult problem OBJECTIVE: To explore the stability of modified threaded Kirschner wire in the treatment of ulnar coronoid process fracture using finite element analysis. METHODS: Thin layer 128-row CT was applied to scan the elbow of one healthy male volunteer. Ulnar coronoid process Regan-Morrey II type fracture model was established using the software such as Mimics 21.0. The models of ordinary Kirschner wire (1.2 mm) and modified threaded Kirschner wire (1.2 mm) were established by Unigraphics NX 10.0 software. The above three kinds of model data were imported into ANSYS Workbench software to generate the ulnar coronoid process Regan-Morrey II type fracture model of ordinary Kirschner wire fixation (ordinary wire group) and the ulnar coronoid process Regan-Morrey II type fracture model of modified threaded Kirschner wire fixation (threaded wire group). The anti-pull-out simulation test, anti-horizontal displacement simulation test and anti-rotational displacement simulation test were carried out for both groups of models. The displacement and stress changes of fracture blocks were recorded, and the variation curves were plotted and Mises stress nephogram was obtained. RESULTS AND CONCLUSION: (1) In the anti-pull-out simulation test, the maximum displacement and the maximum stress of the ordinary wire group were 3.96 mm and 93.2 N, respectively. The maximum displacement and the maximum stress of threaded wire group were 0.20 mm and 177.6 N, respectively. The stress distribution of the threaded wire group was slightly more concentrated than that of the ordinary wire group. (2) In the anti-horizontal displacement simulation test, the maximum displacement and the maximum stress of the ordinary wire group were 0.55 mm and 199.2 N, respectively. The maximum displacement and maximum stress of the threaded wire group were 0.05 mm and 573.7 N, respectively. The stress distribution of the threaded wire group was slightly more concentrated than that of the ordinary wire group. (3) In the anti-rotational displacement simulation test, the maximum displacement and the maximum stress of the ordinary wire group were 3.75 mm and 332.2 N, respectively. The maximum displacement and the maximum stress of the threaded wire group were 0.25 mm and 225.6 N, respectively. The stress distribution of the threaded wire group was slightly more concentrated than that of the ordinary wire group. (4) The experiment proves that the modified threaded Kirschner wire has better stability in fixation of ulnar coronoid process fracture [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of South China Normal University (Natural Science Edition) / Huanan Shifan Daxue Xuebao (Ziran Kexue Ban) is the property of Journal of South China Normal University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of High Pressure Physics is the property of Chinese Journal of High Pressure Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the problems of lap spacing optimization for ER120S-G high-strength steel based on wire and arc additive manufacturing process, the pulsed gas metal arc welding (GMAW-P) processes were adopted to perform Canny edge extraction and Gaussian smoothing filtering for 5 sets of single-layer weld passes, and different functions were selected to fit the single-pass morphology. Conventional lap model and optimized slant-top lap model were compared, and the optimal lap spacing of them was calculated. The results show that, the sine function fits the weld contour best in the GMAW-P process of high-strength steel, and the optimal lap spacing from the optimized slant-top lap model is as 0.66 times of the weld width. Based on the above results, multi-layer multi-pass bulk samples were fabricated, and the surface quality is good and without obvious defects. The bulk mainly contains needle ferrite, granular bainite, and M-A elements. The tensile strength is anisotropic. [ABSTRACT FROM AUTHOR]

Focusing on the fluctuation problem of torsion property of steel wire after galvanizing in practice， microstructure evolution of the wire in the drawing， hot-galvanizing and torsion processes was systematically characterized and analyzed in this work. The results show that in the processes of drawing and torsion of the wire， the sorbite sheet is distorted， the lamellar spacing is reduced， the cementite sheet is broken， the small cementite particles are dissolved， and dislocation density greatly increases. The hot-galvanizing process can dissolve the small-sized cementite particles， eliminate the internal stress and reduce the dislocation density in the wire. The comprehensive effects of cementite sheet breakage， cementite particle dissolution， sorbite lamellar spacing and dislocation density lead to the performance difference in the process of steel wire torsion. [ABSTRACT FROM AUTHOR]

In this paper, the effect of the process parameters of reciprocating diamond wire saw on the surface quality of the (001) plane β-Ga2 O3 single crystal was investigated. According to the theory of the indentation fracture mechanics, the abrasive behavior and material removal mechanism in the process of cutting β-Ga2 O3 single crystal with diamond wire saw were investigated. The influence of the cutting direction on the surface quality of the (001) plane β-Ga2 O3 single crystal was analyzed from the aspect of anisotropy, SEM and SJ-210 roughness measuring instrument were used to explore the effect of process parameters on the quality of wafer surface after diamond wire saw. The experimental results show that the depth of subsurface damage layer can be reduced and the surface quality of the wafer can be effectively improved by increasing the wire speed or decreasing the feed rate. [ABSTRACT FROM AUTHOR]

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Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the autonomous valet parking path planning problems for the wire-four-wheel steering vehicles, an autonomous valet path planning method with adaptive ability to dynamic obstacles was proposed. Firstly, the grid map which might describe the environmental information of parking lot was used to transform the autonomous valet parking path planning problem in continuous state space into that in discrete state space, and the isotropic circular structure elements were used to expand the grid map to keep a safe distance between the planned autonomous valet parking path and the obstacles. Then, the D* Lite algorithm was used to plan the global autonomous valet parking path with adaptive ability to dynamic obstacles, as well the dynamic window method and the arc-line combination method were used to plan the local autonomous valet parking path, which met the kinematic and mechanical constraints of the wire-four-wheel steering vehicles and might guide the vehicles to enter the oblique parking space safely. Finally, the feasibility of the proposed method was verified by simulation, and the results show that the proposed method may plan a feasible path to guide the vehicles into the target oblique parking space safely in the presence of dynamic obstacles. [ABSTRACT FROM AUTHOR]

BACKGROUND: There are few studies on dynamic biomechanical analysis of Kirschner wire tension band steel wire in different winding methods for the treatment of transverse patella fractures. OBJECTIVE: To analyze the biomechanical difference between the “8”-shaped Kirschner wire tension band fixation and the “0”-shaped Kirschner wire tension band for the treatment of transverse patella fractures in the complete gait cycle using three-dimensional reconstruction technology METHODS: Based on the CT scan data of the human knee joint, Mimics, Geomagic Studio, Hypermesh and Abaqus and other three-dimensional reconstruction softwares were used to establish the “8” and “0” shape Kirschner wire tension band to treat the finite element model of the patella transverse fracture. A complete gait cycle of the knee joint after surgery was simulated by loading the material properties, setting boundary conditions, applying loads and other operations. The difference in displacement and stress between the two fixed models was analyzed. RESULTS AND CONCLUSION: (1) In the complete gait cycle, the change of stress value was positively correlated with the change of buckling angle, and the maximum stress reached at 70% of the gait cycle. In the same gait instant, the stress of each component of the “0” model was less than that of the “8” model. (2) The displacement value of each component of the two models increased with the increase of the flexion angle during a complete cycle, and reached the peak displacement at 70% of the gait cycle. In the same gait instantaneously, the “0”-shaped model was different. The displacement values of the components were all smaller than those in the “8” model. At the peak of the displacement, the displacement values of the patella, Kirschner wire and steel wire of the “0” model were 10%, 11%, and 13% smaller than those of the “8” model. (3) The results show that during the complete gait cycle, the high stress areas of the two tension band models are mainly concentrated near the patella fracture line and the contact part of the internal fixation, but the stress peak value of each component in the “0” model is less than “8”-shaped model, and it is better than the “8”-shaped tension band model in terms of the stability of the fracture end and internal fixation, and has a better biomechanical effect. [ABSTRACT FROM AUTHOR]

The fine microstructure in high carbon galvanized steel wires from different manufacturers at domestic and abroad were experimentally characterized and compared. The results show that the microstructure of the domestic steel wires has apparently difference with that of the imported ones, in terms of the distribution of inclusion sizes, the thickness of galvanized layer, the spacing of sorbite lamella, cementite morphology, dislocation density, and etc. For instance, the percentage of the inclusions with the equivalent diameter less than 5 µm can be up to 90. 6% in the imported wire, compared with 85. 4% and 88. 0% in the domestic ones. The Zn-Fe alloy layer in the galvanized layer of the domestic wire is thicker and the coated layer is more loose. Moreover, the sorbite lamellar spacing of the domestic wire is larger and the distribution is more dispersed. It is also found that in the domestic wire, the dissolution of cementite is more serious, the number of granular and short-rod cementite particles increase significantly, and the dislocation density is to times than that of the imported one. The microstructural differences above lead to the poor performance and unstable quality of the domestic steel wire. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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In order to study the influence of one broken wire on the stress distribution of other wires and the overall bearing capacity of the steel strand, a solid model off 1x7 grade 1860 steel strand was established in SolidWorks. HyperMesh was applied for mesh division and ANSYS Workbench was used for analysis. Different boundary conditions and model geometry were conduced to simulate the breaking effect off the side and middle wires. The results were compared with the existing literatures to verify the correctness of the finite element analysis. The results show that the fracture of the middle wire has the effect on the stress off the steel strand, and the stress growth and distribution have the same law as before wire fracture. After the fracture of the side wire, the stress off the adjacent wire was redistributed, which leads to a greater increase of the stress of the adjacent wire; and it enters the plastic development stage easier than other wires, resulting in a greater reduction off the bearing capacity. [ABSTRACT FROM AUTHOR]

An adaptive backstepping control method was proposed based on the facts that the tension control systems of the multi-wire saw had the control characteristics of strong nonlinearity of Coulomb friction and the swing angle coupling, parametric uncertainties susceptible to diameter changes of the winding reel. The controllers combined with experimental identification method and the adaptive controller design method to simplified analyse multi-axis motor synchronization control system and estimate unknown parameters online, the globally asymptotic stability and boundedness of the control systems was guaranteed by using Lyapunov stability theory. The experimental results indicate that the proposed adaptive controller may achieve multi-axis synchronous control with small swing angle and better tension control accuracy. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Hebei University of Science & Technology is the property of Hebei University of Science & Technology, Journal of Hebei University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to study the heat transfer mechanism of hot metal particles formed by wire short-circuit melting to surface forest fuel, in this paper, the finite element analysis technology was used to establish the heat transfer simulation model between hot metal particle and fuel on ground based on the heat transfer theory. Taking hot metal particle as the heat source, considering the effects of heat conduction, convection and radiation, the effects of particle material, ambient temperature, ratio of landing temperature to melting point, multiple of particle center embedding depth and particle radius on the heating process of fuel were analyzed by orthogonal test. The results showed that material, ratio of landing temperature to melting point and radius were the main factors affecting ignition, and copper particles had stronger ignition ability to fuel. This study provides a reference for avoiding forest fire caused by hot metal particle. [ABSTRACT FROM AUTHOR]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cold stress of livestock easily occurs in open sheds of cold areas during winter, due mainly to the relatively low thermal insulation under the low temperature conditions. As such, cold drinking water can further deteriorate the health and growth of young livestock. The objective of this study was to investigate the effect of drinking warm water in winter on the health and growth performance of weaned rabbits. A total of 180 weaned rabbits (47 days of age) with similar body weight (initial body weight 1.2±0.1 kg) were randomly assigned to two groups, either warm water (WW) or cold water (CW) (90 rabbits in each group). An electrical heating wire was also used to heat the warm water, where the water pipe was covered with insulated foam coating. A thermostatic controller was selected to remain at a constant temperature (35.5 ± 1.1 ◦C) during the experiment. The cold water was prepared at (5.8 ± 2.3)◦C without heating. A 48-day test was carried out to measure various indicators. The results showed that: 1) The indoor average air temperature was (8.9±3.2)℃ during the experiment. The average daily weight gain of rabbits in warm water group was significantly higher than that in cold water group during 47-58 days and 47-94 days, respectively, by 15.11 kg/d and 1.94 kg/d (P<0.05).. 2) The feed-weight ratio of rabbits was significantly lower in the warm water group than that in the cold water group during 47～58 days (18.2%) (P < 0.05). But there was no significant difference during the rest. In addition, the risk of diarrhea in rabbits drinking warm water was significantly reduced by 25.6% during 47～94 days (P < 0.05), compared with the cold water group. The expressions of thyroid hormone receptor α and β (THR α and β) in jejunum were significantly down-regulated on 70 days in rabbits drinking warm water (P < 0.05). 3) The contents of immunoglobulin A (IgA) and total protein (TP) in serum increased significantly for the rabbits drinking warm water, with the increase of age, especially on 82 days (P < 0.05). Moreover, the abundance of Roseburia increased in the cecum of rabbits on 82 days in the warm water group, relating to nutrient digestion and absorption, indicating 6.9 times higher than that of 58-day old rabbits (P < 0.05). Consequently, the constant temperature drinking system in the open sheds in winter can be expected to improve the immunity, intestinal digestion, and absorption capacity, thereby promoting the growth and health of weaned rabbits. The finding can provide theoretical support to improve the survival rate and production efficiency of weaned rabbits in open houses in cold areas. [ABSTRACT FROM AUTHOR]

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Traumatic dislocation of sternoclavicular joint is a rare disease in orthopedics, which can cause misdiagnosis and improper treatment. Its operation technology is constantly improving, mainly because of the improvement of the internal objects. OBJECTIVE: To explore the new progress in the diagnosis and treatment of traumatic dislocation of sternoclavicular joint, and to summarize the key points and the advantages and disadvantages of operation with various implants. METHODS: The Chinese database of Wanfang and China National Knowledge Infrastructure was searched by the first author. The key words were “dislocation of sternoclavicular joint; biomechanics; implants; internal fixation; tendon reconstruction; complications; prognosis”. Simultaneously, the English database of PubMed was searched, with the search term of “dislocation of sternoclavicular joint; biomechanics; implant; internal fixation; tendon reconstruction; complications; prognosis”. The retrieval period was from July 2010 to February 2020. RESULTS AND CONCLUSION: (1) Traumatic dislocation of sternoclavicular joint is a kind of trauma which is easy to be missed and may be fatal. Computed tomograhy and B-ultrasound can be used to confirm the diagnosis. Magnetic resonance imaging can show the damage of mediastinum structure. (2) Surgical treatment methods include Kirschner wire tension band internal fixation, hook plate internal fixation, locking plate internal fixation, ligament strengthening and reconstruction technology, joint replacement and so on. The fixation strength of Kirschner wires and steel wires is unsatisfactory and its complication rate is high, but they can be used in juvenile patients. The cross joint steel plate does not meet the biomechanical requirements of the fretting joint, so it is difficult to achieve firm fixation. The hook steel plate belongs to the built-in object of elastic fixation, and the disadvantage lies in the abrasion and stimulation of the bone caused by the tail hook structure. More and more attention has been paid to ligament reconstruction technology, which not only meets the needs of strength, but also conforms to the characteristics of biomechanics. [ABSTRACT FROM AUTHOR]

BACKGROUND: The use of elastic nails to treat children with unstable fractures or heavier children often results in shortening, angular or rotational deformities. OBJECTIVE: To provide a theoretical basis for internal fixation choice for femoral long oblique fracture by elastic nails combined with end caps or wire using biomechanical test. METHODS: An identical length oblique midshaft fracture was created in eight small adult cadaveric femurs harvested from four donors. Two 3.5-mm titanium elastic nails were introduced intramedullary into all femur models. According to the different fracture fixations, all models were divided into four groups (group A: titanium elastic nail, group B: titanium elastic nail+wire, group C: titanium elastic nail+caps, group D: titanium elastic nail+wire+caps). Nondestructive axial compression, four-point bending and torsion tests were conducted. Stiffness, displacement and torque were analyzed. RESULTS AND CONCLUSION: (1) In the axial compression tests, stiffness was increased by 509% and displacement was decreased by 74% using the titanium elastic nail+cap combination compared with titanium elastic nail alone (group A) (P < 0.01). (2) The titanium elastic nail+wire combination (group B) showed larger stiffness (P < 0.01) and smaller displacement (P < 0.01) in the sagittal plane bending test; and as well as larger stiffness (P < 0.01) and smaller displacement (P < 0.01) in coronal plane bending test; and larger stiffness in torsion test (P < 0.01). The end caps with wire in group D improved the stiffness significantly in all directions. (3) The results have demonstrated that end caps fixation helps to increase the axial stability of the long oblique fracture model, and combined wire fixation increases the structural stability under torsional and bending loads, which provides a good reference for clinical treatment of children with unstable femoral shaft fractures [ABSTRACT FROM AUTHOR]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Harbin University of Science & Technology is the property of Journal of Harbin University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Wool Textile Journal is the property of National Wool Textile Science & Technology Information Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A spiral micro-milling cutter with micro-texture on the flank is fabricated on a five-axis low-speed wire-cut electrical discharge machining (WEDM) with a rotary mechanism. A theoretical model for cutting force of micro-edge unit of spiral micro-milling cutter with micro-texture was established， and a comparative experiment of micro-textured micro-milling cutter and conventional micro-milling cutter was carried out. The results show that the cutting force of the micro-textured spiral micro-milling cutter is reduced by 30%-40% compared with that of the conventional tool. Under the same processing conditions， the surface roughness of the micro-textured spiral micro-milling cutter is reduced to 0.745μm， while the surface roughness processed by the conventional micro-milling cutter is 1.130μm. [ABSTRACT FROM AUTHOR]

Copyright of China Textile Leader is the property of China Textile Information Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)