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Exploring the Dual Subjectivity of Kindergarten's Self-made Play and Teaching Aids Activities from the Perspective of Children's Play Development in China
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作者 Yuwei Zhao 《教育技术与创新》 2024年第1期1-9,共9页
The joint development of teachers and young children is the basis for promoting the development of high-quality preschool education in the new era,and encouraging early childhood teachers to make playthings according ... The joint development of teachers and young children is the basis for promoting the development of high-quality preschool education in the new era,and encouraging early childhood teachers to make playthings according to local conditions is both the fine tradition of China's early childhood education and the direct orientation of China's preschool education policy.Homemade play and teaching aids are some of the methods often used in kindergartens,which skillfully combine young children's daily life objects with toys and early childhood teaching,not only enriching the collective activities of young children but also cultivating children's abilities in various aspects.Kindergarten homemade"play and teaching aids"for early childhood teachers and children have their special educational significance and value,therefore,this paper is based on the children and teachers double subject basis,discussing the homemade"play and teaching aids"for children and teachers of the double subject meanings,and puts forward the realization of the This paper discusses the double-subjective meaning of homemade teaching aids for children and teachers on the basis of the double-subjective foundation of children and teachers,and puts forward specific suggestions for realizing the double-subjectivity of kindergarten homemade teaching aids to enrich the theoretical value and practical significance of homemade teaching aids,to provide theoretical references and support for the relevant staff. 展开更多
关键词 self-made playthings Double subjectivity KINDERGARTEN China
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Observation on Curative Effect of Self-made Wubeizi Decoction Combined with rhaFGF in Promoting Postoperative Wound Healing in Patients with Anal Fistula
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作者 Yingnan YANG Dan GAN +2 位作者 Zhiqiang YUAN Dongqin WANG Yu CHEN 《Medicinal Plant》 CAS 2023年第3期74-77,81,共5页
[Objectives]To explore the curative effect of Self-made Wubeizi Decoction combined with recombinant human acidic fibroblast growth factor(rhaFGF)in promoting postoperative wound healing in patients with anal fistula.[... [Objectives]To explore the curative effect of Self-made Wubeizi Decoction combined with recombinant human acidic fibroblast growth factor(rhaFGF)in promoting postoperative wound healing in patients with anal fistula.[Methods]A total of 82 patients with anal fistula who underwent anal fistula resection+use of setons in Luodian Hospital during January and March of 2020 were randomly divided into observation group and control group with 41 cases in each group.The control group was given rhaFGF external application regimen,and the observation group was treated with Self-made Wubeizi Decoction on the basis of the control group.After 3 weeks of treatment,the differences in curative effects of TCM syndromes were compared between the two groups.Besides,the changes in TCM symptom scores,inflammatory mediators[interleukin-12(IL-12),tumor necrosis factor-α(TNF-α),interferon-γ(IFN-γ)],anorectal functions[anal resting pressure(ARP),maximal systolic pressure(MSP)and maximum tolerated volume(MTV)of the anal canal],quality of life[GQOLI-74 scores]were compared.[Results]After 3 weeks of treatment,the total effective rate of the observation group was significantly higher than that of the control group(P<0.05);the levels of TCM symptom scores,IL-12,TNF-α,IFN-γ,ARP,MSP,and MTV in both groups were significantly lower than those before treatment,and these levels in the observation group was significantly lower than that in the control group at the same time(P<0.05).The GQOLI-74 scores of both groups were significantly higher than those before treatment,and the observation group was significantly higher than the control group(P<0.05).[Conclusions]The Self-made Wubeizi Decoction combined with rhaFGF therapy has a significant effect in promoting postoperative wound healing in patients with anal fistula.It can effectively inhibit the local inflammation of patients,facilitate the recovery of anorectal function and improve the quality of life,thus has high clinical application value. 展开更多
关键词 self-made Wubeizi Decoction Recombinant human acidic fibroblast growth factor(rhaFGF) Anal fistula Anal fistula resection Wound healing Inflammatory mediators Anorectal function Quality of life
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Process Analysis of Mobile Fermentation of Spent White Hypsizygus marmoreus Substrate with Self-made Mobile Fermentation Bag
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作者 罗茂春 林标声 +1 位作者 邱丰艳 陈柳花 《Agricultural Science & Technology》 CAS 2016年第4期829-832,共4页
The self-made mobile fermentation bag for spent white Hypsizygus marmoreus substrate was developed, and the relevant fermentation process was studied. The results showed that under the condition of single addition of ... The self-made mobile fermentation bag for spent white Hypsizygus marmoreus substrate was developed, and the relevant fermentation process was studied. The results showed that under the condition of single addition of Lactobacillus,nitrogen-free extract was degraded into lactic acid, leading to decreased pH value.On day 10, the fermentation effect reached the best with Lactobacillus abundance of 5.12×10~7/ml, lactic acid content of 0.48% and strong acid flavor. At this time, the fermentation material was moist without mildew and agglomeration, and was suitable for livestock and poultry. However, after 10 days, undesirable acids and mildew generated, a large amount of lactic acid bacteria died, and the fermentation material turned black and agglomerated, and became unsuitable for feeding livestock and poultry. Throughout the fermentation process, the pH value first decreased continuously until to 4.0, and then remained stable. During the fermentation of spent white H. marmoreus substrate, the nitrogen-free extract and crude fiber contents decreased, the crude protein content increased, while other indicators remained unchanged. 展开更多
关键词 self-made fermentation bag Mobile fermentation Spent white Hypsizy gus marmoreus substrate Fermentation analysis
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Severe skeletal bimaxillary protrusion treated with micro-implants and a self-made four-curvature torquing auxiliary: A case report 被引量:1
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作者 Rui Liu Wan-Bang Hou +4 位作者 Ping-Zhu Yang Lin Zhu Yong-Quan Zhou Xia Yu Xiu-Jie Wen 《World Journal of Clinical Cases》 SCIE 2021年第3期722-735,共14页
BACKGROUND Bimaxillary protrusion is a clinically common dentofacial deformity,particularly among Chinese patients.This kind of malformation can severely affect facial esthetics and,even in mild cases,is difficult to ... BACKGROUND Bimaxillary protrusion is a clinically common dentofacial deformity,particularly among Chinese patients.This kind of malformation can severely affect facial esthetics and,even in mild cases,is difficult to correct without surgery.Unfortunately,many patients abandon treatment because of fear of surgery.Here,we describe a case of severe skeletal bimaxillary protrusion treated with nonsurgical orthodontic treatments,highlighting an alternative treatment option.CASE SUMMARY A 31-year-old woman wished to address a severe protrusion profile(approximately 8 mm overbite)and gummy smile.Cephalometric analysis and superimposition showed a severe skeletal class II pattern with a mandibular retrusion,and proclined and protrusive mandibular incisors.Panoramic radiograph showed a missing mandibular right third molar.A diagnosis of severe bimaxillary dentoalveolar protrusion was made.Taking into account the patient’s fear of orthognathic surgery,she accepted the proposed alternative treatment using micro-implants and a self-made four-curvature torquing auxiliary.The treatment allowed for maximal en masse anterior tooth retraction,proper relocation of incisors,and alleviation of the skeletal class II pattern.Esthetically,the patient’s lip protrusion was significantly decreased as was the overjet(from 10.5 mm to 1.8 mm),and the results remained stable throughout the 2-year followup.CONCLUSION Nonsurgical treatment using micro-implants and a four-curvature torquing auxiliary may benefit severe cases of skeletal bimaxillary protrusion in adults. 展开更多
关键词 ORTHODONTICS Bimaxillary protrusion Micro-implants self-made fourcurvature torquing auxiliary Teeth Case report
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Self-made wire loop snare successfully treats gastric persimmon stone under endoscopy
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作者 Wen Xu Xiao-Bo Liu +2 位作者 Sheng-Bao Li Wei-Ping Deng Qiang Tong 《World Journal of Clinical Cases》 SCIE 2022年第19期6428-6436,共9页
BACKGROUND Large gastric persimmon stones are generally resistant to standard endoscopic treatments.We applied an alternative endoscopic method using a hand-made snare for the treatment of large gastric phytobezoars.A... BACKGROUND Large gastric persimmon stones are generally resistant to standard endoscopic treatments.We applied an alternative endoscopic method using a hand-made snare for the treatment of large gastric phytobezoars.AIM To explore the clinical efficacy of a self-made wire loop snare to treat giant gastric persimmon stones.METHODS A retrospective study evaluated the clinical data of 38 patients with gastroliths admitted to Taihe Hospital in Shiyan City,Hubei Province,China,between March 2015 and October 2020.The patients were divided into observation(n=23)and control(n=15)groups.Patients in the observation group were treated with selfmade wire loop snares for lithotripsy,and patients in the control group were treated with traditional foreign body forceps,snares,injection needles,and other tools.Successful stone removal,treatment time,and hospital stay were compared.RESULTS The average operating time was significantly shorter(P<0.001)in the observation group(53.4 min)than that in the control group(172.8 min).The average hospital stay of the observation group(5.4 d)was significantly shorter(P<0.001)than that in the control group(10.3 d).Successful one-time treatment was significantly more frequent(P<0.001)in the observation group(87%)than in the control group(7%).CONCLUSION Self-made guidewire loop snares were successfully used to treat gastrolithiasis, and were significantly more effective than foreign body forceps, snares, and other traditionalmethods. 展开更多
关键词 Gastric persimmon Phytobezoars self-made snare ENDOSCOPY Treatment
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An Improved Elite Slime Mould Algorithm for Engineering Design 被引量:1
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作者 Li Yuan Jianping Ji +3 位作者 Xuegong Liu Tong Liu Huiling Chen Deng Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期415-454,共40页
The Swarm intelligence algorithm is a very prevalent field in which some scholars have made outstanding achievements.As a representative,Slime mould algorithm(SMA)is widely used because of its superior initial perform... The Swarm intelligence algorithm is a very prevalent field in which some scholars have made outstanding achievements.As a representative,Slime mould algorithm(SMA)is widely used because of its superior initial performance.Therefore,this paper focuses on the improvement of the SMA and the mitigation of its stagnation problems.For this aim,the structure of SMA is adjusted to develop the efficiency of the original method.As a stochastic optimizer,SMA mainly stimulates the behavior of slime mold in nature.For the harmony of the exploration and exploitation of SMA,the paper proposed an enhanced algorithm of SMA called ECSMA,in which two mechanisms are embedded into the structure:elite strategy,and chaotic stochastic strategy.The details of the original SMA and the two introduced strategies are given in this paper.Then,the advantages of the improved SMA through mechanism comparison,balance-diversity analysis,and contrasts with other counterparts are validated.The experimental results demonstrate that both mechanisms have a significant enhancing effect on SMA.Also,SMA is applied to four structural design issues of the welded beam design problem,PV design problem,I-beam design problem,and cantilever beam design problem with excellent results. 展开更多
关键词 Slime mould algorithm metaheuristic algorithm continuous optimization chaos random strategy engineering design
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Protective Effects of Self-made Compound Taoren Danshen Decoction on Rats with Acute Liver Injury
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作者 Yuman GUAN Kefeng ZHANG +2 位作者 Ya GAO Jiani LI Lin ZHANG 《Medicinal Plant》 CAS 2018年第5期107-110,共4页
[Objectives] To study the protective effects of self-made Compound Taoren Danshen Decoction( CTDD) on acute liver injury induced by D-galactosamine in rats,and to explore its mechanism. [Methods]An acute liver injury ... [Objectives] To study the protective effects of self-made Compound Taoren Danshen Decoction( CTDD) on acute liver injury induced by D-galactosamine in rats,and to explore its mechanism. [Methods]An acute liver injury model was established by intraperitoneal injection of 500 mg/kg of D-galactosamine. The ALT,AST,MDA,SOD and GSH-Px in serum,as well as serum TNF-α,IL-1β and IL-6 levels were measured,and liver tissue lesions were observed under microscope. [Results] CTDD can significantly reduce ALT,AST and MDA levels,increase SOD,GSH-Px activity,and significantly reduce serum TNF-α,IL-1β and IL-6 levels,and improve liver tissue lesions.[Conclusions]CTDD has a protective effect on D-galactosamine-induced acute liver injury in rats,and its mechanism may be related to inhibition of oxidative stress and inflammatory reaction. 展开更多
关键词 self-made COMPOUND Taoren DANSHEN Decoction(CTDD) D-GALACTOSAMINE Acute liver injury Oxidative stress INFLAMMATORY reaction
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Observation on the Effect of Umbilical Therapy of Herbal Medicine Combined with Self-Made Dysmenorrhea Paste on Primary Dysmenorrhea
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作者 Wen-Ming Cao Xiu-Rong Wang 《Psychosomatic Medicine Research》 2020年第1期1-7,共7页
Objective:To investigate the clinical effect of self-made dysmenorrhea paste combined with umbilical therapy of herbal medicine on primary dysmenorrhea.Methods:160 patients with primary dysmenorrhea were recruited fro... Objective:To investigate the clinical effect of self-made dysmenorrhea paste combined with umbilical therapy of herbal medicine on primary dysmenorrhea.Methods:160 patients with primary dysmenorrhea were recruited from Changle People’s Hospital.Participants were randomly divided into control group and treatment group,with 80 cases in each group.The control group were administered the dysmenorrhea paste sold on the market for 5 days during three menstruation cycles,and the treatment group was given the umbilical therapy of herbal medicine combined with self-made dysmenorrhea paste.The outcome was the intensity of menstrual pain measured by using the visual analogue scale,TCM symptom score and dysmenorrhea symptom score of patients,responder rate.The clinical outcomes were measured on each menstrual cycle at baseline,treatment course(3 cycles),and follow-up period.Results:In this study,there was no significant difference in age and severity of disease between the two groups before treatment.After treatment,VAS score,TCM symptom score and dysmenorrhea symptom score of patients in both groups decreased.The total effective rate was 90.75%in the treatment group and 81.25%in the control group.Conclusion:The treatment of primary dysmenorrhea patients with self-made dysmenorrhea paste combined with application of drugs and moxibustion naval-button method has a significant clinical effect.This method can reduce the pain of patients,improve the quality of life of patients,and homemade dysmenorrhea paste has a good taste,long shelf life,easy to carry,and is worthy of promotion and application. 展开更多
关键词 self-made DYSMENORRHEA PASTE DRESSING and moxibustion UMBILICUS Primary DYSMENORRHEA Therapeutic EFFECT
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Effect of self-made exhaust plaster on patients with gastrointestinal dysfunction after gynecological operation
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作者 Wen-Ming Cao Xiu-Rong Wang Xiao-Xia Wang 《Psychosomatic Medicine Research》 2020年第2期54-59,共6页
Objective:To explore the effect of self-made exhaust patch(SMEP)on gastrointestinal dysfunction after gynecological operation.Methods:A total of 200 patients with gynecological operation in the gynecological ward of S... Objective:To explore the effect of self-made exhaust patch(SMEP)on gastrointestinal dysfunction after gynecological operation.Methods:A total of 200 patients with gynecological operation in the gynecological ward of Shandong Changle People's Hospital were randomly divided into the control group(n=100)and the treatment group(n=100).The recovery time of bowel sounds,the time of first anal exhaust,the duration of abdominal distention,the duration of abdominal pain,the incidence of abdominal distention and abdominal pain and linical efficacy of SMEP were observed.Results:Compared with the control group,the recovery time of gastrointestinal function and the first anal exhaust time in the treatment group were shorter;the duration of abdominal distention and abdominal pain in the treatment group were shorter than those in the control group(P<0.05);Cure rate of abdominal distention in the treatment is 62.5%and cure rate of abdominal pain in the treatment is 60%within 72 hours after operation,which is higher than that in the control group(44.%,45.9%).Conclusion:The results showed that the self-made exhaust patch can improve the clinical symptoms of patients after gynecological abdominal surgery,and the self-made exhaust patch had a significant effect on gastrointestinal dysfunction after gynecological surgery,which was worthy of clinical promotion. 展开更多
关键词 self-made exhaust patch Gynecological operation Gastrointestinal dysfunction Abdominal distention
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Clinical observation on TCM fumigation and washing for treatment of diabetic peripheral neuropathy by self-made water-washing footbath
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作者 Lu Gan Qing Liu +2 位作者 Liping Jin Zheng Yuan Youqiong Zhang 《TMR Clinical Research》 2019年第1期37-42,共6页
the quality of life seriously,and even lead to more servere complications.On the base of the well-controlled blood glucose,improving the symptoms of both lower limbs timely will has positive significance for enhancing... the quality of life seriously,and even lead to more servere complications.On the base of the well-controlled blood glucose,improving the symptoms of both lower limbs timely will has positive significance for enhancing the life quality of patients and preventing complications of limbs.This article makes a comprehensive study on the application of self-made water-washing footbath in the treatment of DPN by Chinese medicine fumigation.From March 2018 to April 2018 in our hospital 20 cases of DPN patients were collected and they were divided into observation group(treated by self-made water-washing footbath with herbs)and control group(treated by conventional barrels),10 cases in each.The results showed that Chinese medicine fumigation on both lower limbs has clinical curative effect to improve the symptoms of arthromyodynia caused by diabetes.It provide an alternative method of external treatment for DPN patients with numbness in both lower limbs which could alleviate their suffering and improve the quality of life significantly. 展开更多
关键词 self-made water-washing footbath Chinese medicine fumigation and washing Diabetic peripheralneuropathy Clinical observation
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基于UG的拖拉机大灯注塑模具设计 被引量:1
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作者 宋芳 《农机化研究》 北大核心 2024年第8期264-268,共5页
以拖拉机大灯为例,分析了UG注塑模具建模的设计方法和工艺方案,建立了拖拉机大灯模型,并完成了拖拉机大灯注塑模具的设计。研究结果表明:经过UG模拟开模出来的塑料件没有出现气泡、变形、缺料和银线等缺陷,整体也没有发现熔合条纹,设计... 以拖拉机大灯为例,分析了UG注塑模具建模的设计方法和工艺方案,建立了拖拉机大灯模型,并完成了拖拉机大灯注塑模具的设计。研究结果表明:经过UG模拟开模出来的塑料件没有出现气泡、变形、缺料和银线等缺陷,整体也没有发现熔合条纹,设计的拖拉机大灯注塑模具满足设计需求。 展开更多
关键词 拖拉机 大灯 UG 注塑 模具
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基于改性PP成型的工控机电路板支撑架注射模设计
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作者 王清 张云 +3 位作者 汪伟芬 熊建武 胡智清 陈黎明 《工程塑料应用》 CAS CSCD 北大核心 2024年第3期97-102,共6页
针对工控机电路板支撑架大型塑件的成型,选用了一种玻纤改性增强聚丙烯(PP)复合材料用于塑件的注射成型。模具结构为三板模结构,分3次开模打开。为保证塑件模腔充填均衡性、饱满性而设计了两个点浇口用于模腔的浇注。针对塑件二级子特... 针对工控机电路板支撑架大型塑件的成型,选用了一种玻纤改性增强聚丙烯(PP)复合材料用于塑件的注射成型。模具结构为三板模结构,分3次开模打开。为保证塑件模腔充填均衡性、饱满性而设计了两个点浇口用于模腔的浇注。针对塑件二级子特征较多,特别是异型螺柱深筋位较多的特点,设计了多个局部镶件用于这些局部特征的成型,在提高局部成型镶件强度的同时,降低了这些成型件的加工难度。针对模腔局部位置排气难点,设置了多个透气镶件以增强排气。设置了锁扣机构、定距拉杆机构用于模具的开模闭模控制;设计了弹料机构用于流道废料的可靠脱模、定位机构以确保塑件的成型精度和模具工作寿命;3个滑块机构用于塑件侧壁直壁及直壁上侧孔的成型与脱模。模具结构形式合理,成型件便于加工且实用可靠,能为同类模具设计提供有益借鉴。 展开更多
关键词 聚丙烯复合材料 玻纤改性 工控机电路板支架 三板模 成型件设计 模具结构
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基于改进黏菌算法的光伏多峰值MPPT控制 被引量:1
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作者 任志玲 毛奕栋 《太阳能学报》 EI CAS CSCD 北大核心 2024年第2期421-428,共8页
针对传统最大功率点跟踪技术在局部遮阴等天气条件下存在无法追踪到全局最大功率点的问题,提出一种基于改进黏菌算法的MPPT控制。首先,对太阳电池模型及多峰值特性进行分析;其次,在黏菌算法中引入领导者策略和基于最优个体的凸透镜反向... 针对传统最大功率点跟踪技术在局部遮阴等天气条件下存在无法追踪到全局最大功率点的问题,提出一种基于改进黏菌算法的MPPT控制。首先,对太阳电池模型及多峰值特性进行分析;其次,在黏菌算法中引入领导者策略和基于最优个体的凸透镜反向学习策略,在提高算法计算精度、收敛速度的同时克服了算法易“早熟”现象;最后,根据光伏阵列最大功率输出特性分别确定算法优化模型、初始化位置及重启机制。仿真与实验结果表明:基于改进黏菌算法的MPPT控制能快速、准确地跟踪到全局最大功率点,有效规避陷入局部最优问题,提高了光伏系统的转换效率。 展开更多
关键词 光伏发电 最大功率点跟踪 优化 局部遮阴 改进黏菌算法
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基于Polyflow正压防护面罩吸塑成型过程
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作者 赵新通 管健晖 张瑞丰 《塑料》 CAS CSCD 北大核心 2024年第3期1-6,共6页
为探究正压防护面罩吸塑成型过程中不同工艺参数组合对其影响。结合实际设计的要求,采用PET材料作为面罩吸塑材料,基于Ployflow,分析不同压力、温度组合的工艺参数及初始板材厚度对面罩吸塑成型的影响。结果表明,利用面积延伸率、厚度... 为探究正压防护面罩吸塑成型过程中不同工艺参数组合对其影响。结合实际设计的要求,采用PET材料作为面罩吸塑材料,基于Ployflow,分析不同压力、温度组合的工艺参数及初始板材厚度对面罩吸塑成型的影响。结果表明,利用面积延伸率、厚度均匀性及面罩成型深度综合分析面罩的吸塑成型质量发现,温度和压力对面罩成型质量的影响较显著。由于板材厚度与成型深度呈负相关,再结合面罩成型深度的要求可知,在符合设计要求的条件下,当工艺参数组合为温度114℃、压力0.65 MPa、PET板材初始厚度为1 mm时,面罩质量最佳。 展开更多
关键词 正压呼吸面罩 吸塑成型 工艺参数 成型深度 板材厚度
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鞍钢8m弧半径小方坯连铸机提速实践
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作者 孙振宇 那廷权 +3 位作者 李叶忠 唐雪峰 王成青 梁祥远 《鞍钢技术》 CAS 2024年第1期55-58,共4页
针对8 m弧半径小方坯铸机拉速低不能满足生产要求的问题,分析了影响铸机提速的主要原因,采取了增加结晶器长度,更新结晶器供水泵,更新二冷水嘴,增大二冷管径以及优化系统温度等措施,铸机拉速由2.8 m/min提高到3.5 m/min,铸坯质量合格率... 针对8 m弧半径小方坯铸机拉速低不能满足生产要求的问题,分析了影响铸机提速的主要原因,采取了增加结晶器长度,更新结晶器供水泵,更新二冷水嘴,增大二冷管径以及优化系统温度等措施,铸机拉速由2.8 m/min提高到3.5 m/min,铸坯质量合格率达到99.95%,实现了小方坯铸机高速稳定生产。 展开更多
关键词 小方坯连铸 拉速 结晶器 二次冷却
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汽车空调控制面板双色倒装热流道注射模设计
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作者 张跃飞 刘敬祺 +2 位作者 胡光良 朱少军 严胜义 《工程塑料应用》 CAS CSCD 北大核心 2024年第7期116-123,共8页
汽车空调控制面板作为人机交互界面不可或缺的操作零件,设计时为了集成使用功能和外观美感等多重要求,一般设计为双色注塑件。以某汽车内饰空调控制面板为例,设计了一副双色倒装热流道注塑模,并详细介绍了零件结构特征、模具结构设计方... 汽车空调控制面板作为人机交互界面不可或缺的操作零件,设计时为了集成使用功能和外观美感等多重要求,一般设计为双色注塑件。以某汽车内饰空调控制面板为例,设计了一副双色倒装热流道注塑模,并详细介绍了零件结构特征、模具结构设计方案及工作原理。由于零件结构特殊性和注塑材料成型温度差异,塑件在成型过程中采用传统正置成型方案时表面易出现串色、印痕等缺陷,成型良品率较低,故模具采用倒装结构设计方案,即第一色先成型茶色透明的聚碳酸酯(PC)外观部分,再成型第二色黑色的PC/丙烯腈-丁二烯-苯乙烯塑料(ABS)基体部分。基于模具的倒装结构,其第一、二色均采用热流道系统进料,同时为了确保零件顺利生产、顶出顺畅,在第一色子模内设置拉料柱和预压型推出机构,第二色子模具的定模侧设计了斜顶和顶针联合顶出机构,利用油缸驱动实现塑件脱模。实验证明,该倒装双色热流道注塑模整体结构稳定可靠,塑件批量生产质量满足设计要求。 展开更多
关键词 空调控制面板 双色注塑 倒装模具 热流道 联合顶出机构
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半预制预应力UHPC-S-NC盖梁静力性能试验及理论分析
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作者 李立峰 谢坤 +3 位作者 刘慈军 邵旭东 陈涛 唐嘉豪 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第7期177-191,共15页
为解决大悬臂盖梁吊装重量大且难以实现预制拼装的技术难题,利用超高性能混凝土(Ultra-High Performance Concrete,UHPC)优异的力学性能,提出了采用由UHPC、钢板和型钢(Steel,S)制作的槽形组合结构作为永久模板,架设就位后浇筑普通混凝... 为解决大悬臂盖梁吊装重量大且难以实现预制拼装的技术难题,利用超高性能混凝土(Ultra-High Performance Concrete,UHPC)优异的力学性能,提出了采用由UHPC、钢板和型钢(Steel,S)制作的槽形组合结构作为永久模板,架设就位后浇筑普通混凝土(Normal Concrete,NC)的新型半预制预应力UHPC-S-NC盖梁.为研究其抗裂性能、刚度并对其安全性进行评估,结合实际工程,设计一片1∶2.5的大比例缩尺模型并进行全过程静力加载测试,获得了试验梁的变形特征、开裂荷载、裂缝开展、分布规律和应变等关键试验数据.分析了试验梁裂缝分布和应变发展规律;考虑材料塑性应力-应变关系,提出了结构UHPC层和NC层的开裂弯矩计算模式和计算方法;并根据截面平衡条件提出了组合结构的抗弯承载力计算模式,同时,依据规范对结构抗剪承载力的计算模式进行了探究.结果表明:新型组合盖梁结构具有施工快捷、装配化程度高等特点;开裂弯矩的计算结果与试验值吻合较好;采用平衡条件和叠加法评估结构的承载力,新型盖梁结构具有足够的承载能力,结果偏于安全;针对实际工程提出了一些具体的结构设计和施工的建议.研究成果可为半预制盖梁的应用提供参考. 展开更多
关键词 桥梁 盖梁 半预制 免拆模 抗裂性能 承载力
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汽车侧裙板数值成型分析及模具设计
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作者 谭安平 李玲 +1 位作者 段扬 骆静 《塑料》 CAS CSCD 北大核心 2024年第2期168-173,177,共7页
汽车侧裙板长度约为1 m,宽度约为0.1 m,卡扣、加强筋、嵌件孔等复杂结构较多,属于大型细长复杂塑件。大型细长复杂塑件成型难度较大,需要采用数值仿真与模具设计相结合的方法,仿真、设计和验证交叉进行、相互渗透。根据产品的特点拟定了... 汽车侧裙板长度约为1 m,宽度约为0.1 m,卡扣、加强筋、嵌件孔等复杂结构较多,属于大型细长复杂塑件。大型细长复杂塑件成型难度较大,需要采用数值仿真与模具设计相结合的方法,仿真、设计和验证交叉进行、相互渗透。根据产品的特点拟定了3种进浇方案,仿真结果表明,方案Ⅲ(9点进浇)翘曲变形量最小,其值为4.51 mm。通过验证方案Ⅲ的缩水性、填充时间、填充等值线、填充末端时间差及压力差等参数可知,方案Ⅲ填充均匀、末端压力一致、产品无缩水,表面无质量缺陷,为可行方案。根据方案Ⅲ进行模具设计,包括浇注系统、成型零部件、推出机构、冷却系统等。模具设计完毕后对冷却系统进行验证,结果表明,凸凹模的模温温差小于10℃,模温趋于一致,无翘曲变形风险。基于方案Ⅲ的模具设计可作为最终方案,为模具制造和生产提供方向。 展开更多
关键词 汽车侧裙板 浇注系统 优化 冷却系统 模具设计
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基于教学用气动控制微型自动蜡模成型机设计
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作者 陈虎城 何玉林 黄伟 《模具工业》 2024年第8期76-80,共5页
针对现有蜡模成型机体积大、维护成本高,不适用实践教学等问题,设计了基于气动控制的微型自动蜡模成型机,该装置使用压缩空气作为动力源。设计结果表明:装置采用气动增压式驱动方案,空间利用率高,整体尺寸小、质量轻;采用注射机构、合... 针对现有蜡模成型机体积大、维护成本高,不适用实践教学等问题,设计了基于气动控制的微型自动蜡模成型机,该装置使用压缩空气作为动力源。设计结果表明:装置采用气动增压式驱动方案,空间利用率高,整体尺寸小、质量轻;采用注射机构、合模机构等模块式设计,既有利于学生快速掌握成型工艺,又便于学生理解典型工程产品设计思路,实验装置的应用可增加实验项目间关联性,提高学生实践参与度,提升学生工程实践能力。 展开更多
关键词 气动控制 蜡模成型 小型化 实验教学
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基于气动控制的蜡模成型实验装置设计与应用
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作者 陈虎城 赵亮亮 何玉林 《模具工业》 2024年第6期73-76,共4页
针对手动式蜡模成型实验装置操作耗费人力且锁紧效率低,不便于操作的问题,设计了气动控制的蜡模成型实验装置,以气压为动力源,增设模具快速拆装和锁模机构,实现了气压自动压注的效果。实验表明:设计的气动蜡模成型实验装置成型的蜡模效... 针对手动式蜡模成型实验装置操作耗费人力且锁紧效率低,不便于操作的问题,设计了气动控制的蜡模成型实验装置,以气压为动力源,增设模具快速拆装和锁模机构,实现了气压自动压注的效果。实验表明:设计的气动蜡模成型实验装置成型的蜡模效果好,模具拆装和锁模效率比手动驱动方式提高了近3倍;将该装置应用在实验教学中,提高了学生实验参与度,实验反馈效果好。 展开更多
关键词 气动 蜡模成型 实验装置 锁紧机构
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