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Treatment of Synovial Cysts in Relation to the Tibial Tunnel of Anterior Cruciate Ligament Grafts by Filling the Tunnel with Acrylic Cement
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作者 Saint Luc Mungina Sedou Charlène Tshitala Mbombo +6 位作者 Yannick Toko Kiama Kevin Ndangi Ezechiel Nkodia Dieudonné Mwangala Rossyl Kivudi Dominique Saragaglia Luc Mokassa Bakumobatane 《Surgical Science》 2024年第4期289-298,共10页
Introduction: Synovial cyst of the tibial tunnel in connection with anterior cruciate ligament (ACL) reconstruction is a rare but particularly troublesome complication. Medical treatment is often doomed to failure, an... Introduction: Synovial cyst of the tibial tunnel in connection with anterior cruciate ligament (ACL) reconstruction is a rare but particularly troublesome complication. Medical treatment is often doomed to failure, and surgical treatment usually consists of excising the cyst and filling the tunnel with bone. The aim of this study was to evaluate the results of filling the tunnel with acrylic cement. Hypothesis: Filling the tibial bone tunnel with acrylic cement should eliminate communication between the joint cavity and the pre-tibial surface and prevent cyst recurrence. Patients and Methods: This retrospective series is composed of 13 patients, 9 men and 4 women, mean age 48.5 years (31 to 64) operated on between 2011 and 2019 for an intra- and extraosseous synovial cyst consecutive to the tibial tunnel of an ACL graft. Between 1983 and 2016, 12 of the patients had had a bone graft without bone block fixation (DI-DT or Mac Intosh) and one patient, a bone-bone transplant (KJ). The cyst was of variable size, located on the anteromedial aspect of the proximal end of the tibia, and often painful, warranting consultation. At the time of the initial operation, 9 patients had undergone meniscectomies (6 medial, 2 lateral, 1 double). In 7 knees, there were 7 cartilage lesions in the femorotibial and/or patellofemoral compartments (one stage 1 lesion, 2 stage 2 lesions, 4 stage 3 lesions, and no stage 4 lesions). Only 2 knees had neither cartilage nor meniscus lesions. After curettage of the bone tunnel /− removal of the non-resorbed or PEEK interference screw, the tunnel was filled with acrylic cement /− reinforced with a ligament staple to prevent expulsion. All patients underwent regular follow-up consultations until recovery. Results: At a maximum follow-up of 8 years, only 1 cyst recurred, representing a 7.69% failure rate. It was reoperated with another technique, which involved filling the tibial bone tunnel with bone graft taken from a half-bank head. After recovery, the cyst healed definitively. All patients were able to return to their previous activity within 15 days of surgery. Conclusion: Filling the tibial tunnel with acrylic cement reinforced /− with a ligament staple is a reliable and rapid solution for the treatment of intra- and extra-articular synovial cysts in relation to the tibial tunnel of ACL grafts. 展开更多
关键词 Arthro-Synovial Cyst Tibial Tunnel ACL Graft filling Acrylic Cement
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Analysis of the Effectiveness of Modified Non- Traumatic Filling Technology in the Treatment of Pediatric Dental Caries
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作者 Yi Liu 《Journal of Clinical and Nursing Research》 2024年第3期95-100,共6页
Objective:To analyze the effectiveness of modified non-traumatic filling technology in the treatment of pediatric dental caries.Methods:Ninety-seven children with dental caries who were treated in our hospital(Panyu M... Objective:To analyze the effectiveness of modified non-traumatic filling technology in the treatment of pediatric dental caries.Methods:Ninety-seven children with dental caries who were treated in our hospital(Panyu Maternal and Child Care Service Center of Guangzhou)from January 2022 to December 2023 were selected and randomly divided into two groups,with 48 cases in the experimental group and 49 in the control group.The experimental group was treated with modified non-traumatic filling techniques,while the control group was treated with conventional filling techniques.Observation indicators such as the total effectiveness of the treatment,incidence of adverse events,treatment compliance,and pain scores were analyzed after the intervention.Result:After intervention,the total effectiveness of the treatment in the experimental group was higher than that in the control group(P<0.05).The incidence of adverse events in the experimental group was lower than that of the control group(P<0.05).The treatment compliance of patients in the experimental group was higher than that in the control group(P<0.05).The pain score of the experimental group was lower than that of the control group(P<0.05).Conclusion:The application of modified non-traumatic filling technology in the treatment of pediatric dental caries showed good therapeutic outcomes.After the intervention,the child’s symptoms were significantly alleviated,the incidence of adverse events such as filling material falling off was reduced,their compliance was improved,and the pain was relieved.This procedure is worth to be promoted for clinical application. 展开更多
关键词 Improved non-traumatic filling technology Treatment effect Pediatric caries
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Raw Gangue Filling Mining under Construction —A Case Study in China 被引量:1
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作者 Daqing Li Changxiang Wang +4 位作者 Jinjie Xiao Wei Lu Baoliang Zhang Zongkai Li Xiaozhang Tong 《Engineering(科研)》 CAS 2023年第3期176-195,共20页
In order to recover the strip pillar coal resources, reduce the amount of gangue mountain and realize remediation of the goaf environment in the old mining area, the raw gangue filling mining technology was proposed. ... In order to recover the strip pillar coal resources, reduce the amount of gangue mountain and realize remediation of the goaf environment in the old mining area, the raw gangue filling mining technology was proposed. According to the previous practical experience, the feasibility of the implementation of raw gangue filling mining technology in the coal-pressed area was analyzed. Through the filling gangue compaction test, the deformation under different loading stages was obtained. Further, a reasonable prediction of the deformation beyond the experimental limited loading load was made based on the experimental results. Through the deformation source analysis of the whole process of gangue filling, the key factors for controlling deformation before, during, and after filling were determined. Additionally, the proportion of deformation during different stages was quantified. Considering the protection of surface buildings, mining fullness of the working face and mining technology, the production parameters of 1209 and 1210 filling working faces were preliminarily determined. Through numerical simulation, the rationality of mining scheme was verified. Based on the practice of 1209 working face and the key factors to control the deformation of gangue filling, the mining system and process in 1210 working face were optimized. According to the measured surface rock movement, raw gangue filling mining technology can meet the requirements of surface building protection level. Especially, this paper provides a method to quantitatively calculate the equivalent mining height (EMH) of raw gangue filling and its mining deformation, which has reference significance for old mining areas. 展开更多
关键词 Coal Resource Recovery under Construction Raw Gangue filling Mining Principle of Space-Time Control filling System and Process Innovation
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Tuning Active Metal Atomic Spacing by Filling of Light Atoms and Resulting Reversed Hydrogen Adsorption-Distance Relationship for Efficient Catalysis
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作者 Ding Chen Ruihu Lu +11 位作者 Ruohan Yu Hongyu Zhao Dulan Wu Youtao Yao Kesong Yu Jiawei Zhu Pengxia Ji Zonghua Pu Zongkui Kou Jun Yu Jinsong Wu Shichun Mu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期151-162,共12页
Precisely tuning the spacing of the active centers on the atomic scale is of great significance to improve the catalytic activity and deepen the understanding of the catalytic mechanism,but still remains a challenge.H... Precisely tuning the spacing of the active centers on the atomic scale is of great significance to improve the catalytic activity and deepen the understanding of the catalytic mechanism,but still remains a challenge.Here,we develop a strategy to dilute catalytically active metal interatomic spacing(d_(M-M))with light atoms and discover the unusual adsorption patterns.For example,by elevating the content of boron as interstitial atoms,the atomic spacing of osmium(d_(Os-Os))gradually increases from 2.73 to 2.96?.More importantly,we find that,with the increase in dOs-Os,the hydrogen adsorption-distance relationship is reversed via downshifting d-band states,which breaks the traditional cognition,thereby optimizing the H adsorption and H_2O dissociation on the electrode surface during the catalytic process;this finally leads to a nearly linear increase in hydrogen evolution reaction activity.Namely,the maximum dOs-Os of 2.96?presents the optimal HER activity(8 mV@10 mA cm^(-2))in alkaline media as well as suppressed O adsorption and thus promoted stability.It is believed that this novel atomic-level distance modulation strategy of catalytic sites and the reversed hydrogen adsorption-distance relationship can shew new insights for optimal design of highly efficient catalysts. 展开更多
关键词 ELECTROCATALYSIS DFT calculation Interstitial filling Hydrogen evolution Structure–activity relationships
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FGW1, a protein containing DUF630 and DUF632 domains, regulates grain size and filling in Oryza sativa L.
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作者 Yangyang Li Peilong He +7 位作者 Xiaowen Wang Hongyan Chen Jile Ni Weijiang Tian Xiaobo Zhang Zhibo Cui Guanghua He Xianchun Sang 《The Crop Journal》 SCIE CSCD 2023年第5期1390-1400,共11页
Grain filling influences grain size and quality in cereal crops. The molecular mechanisms that regulate grain endosperm development remain elusive. In this study, we characterized a filling-defective and grain width m... Grain filling influences grain size and quality in cereal crops. The molecular mechanisms that regulate grain endosperm development remain elusive. In this study, we characterized a filling-defective and grain width mutant, fgw1, whose mutation increased rice seed width mainly via cell division and expansion in grains. Sucrose contents were higher but starch contents lower in the fgw1 mutant during the grainfilling stage, resulting in inferior endosperm of opaque, white appearance with loosely packed starch granules. Map-based cloning revealed that FGW1 encoded a protein containing DUF630/DUF632domains, localized in the plasma membrane with preferential expression in the panicle. RNA interference in FGW1 resulted in increased grain width and weight, whereas overexpression of FGW1 led to slightly narrower kernels and better grain filling. In a yeast two-hybrid assay, FGW1 interacted directly with the 14–3–3 protein GF14f, bimolecular fluorescence complementation verified that the site of interaction was the membrane, and the mutated FGW1 protein failed to interact with GF14f. The expression of GF14f was down-regulated in fgw1, and the activities of AGPase, StSase, and SuSase in the endosperm of fgw1increased similarly to those of a reported GF14f-RNAi. Transcriptome analysis indicated that FGW1 also regulates cellular processes and carbohydrate metabolism. Thus, FGW1 regulated grain formation via the GF14f pathway. 展开更多
关键词 Seed size Grain filling DUF630/DUF632 Starch synthesis Rice
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Effects of mechanical vibration on filling and solidification behavior, microstructure and performance of Al/Mg bimetal by lost foam compound casting
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作者 Guang-yu Li Feng Guan +3 位作者 Wen-ming Jiang Yuan-cai Xu Zheng Zhang Zi-tian Fan 《China Foundry》 SCIE EI CAS CSCD 2023年第6期469-479,共11页
Al/Mg bimetal was prepared by lost foam solid-liquid compound casting,and the effects of mechanical vibration on the filling and solidification behavior,microstructure and performance of the bimetal were investigated.... Al/Mg bimetal was prepared by lost foam solid-liquid compound casting,and the effects of mechanical vibration on the filling and solidification behavior,microstructure and performance of the bimetal were investigated.Results show that the mechanical vibration has a remarkable influence on the filling and solidification processes.It is found that after mechanical vibration,the filling rate increases and the filling rate at different times is more uniform than that without vibration.In addition,the mechanical vibration also increases the wettability between liquid AZ91D and A356 inlays.The mechanical vibration reduces the horizontal and vertical temperature gradient of the casting and makes the temperature distribution of the whole casting more uniform.Compared to the Al/Mg bimetal without vibration,the shear strength is improved by 39.76%after the mechanical vibration is applied,due to the decrease of the inclusions and Al_(12)Mg_(17) dendrites,and the refinement and uniform distribution of the Mg_(2)Si particles in the interface of the Al/Mg bimetal. 展开更多
关键词 lost foam casting filling and solidification processes Al/Mg bimetal mechanical vibration MICROSTRUCTURE mechanical properties
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Effects of Heat Stress during Seed Filling Stage on Brassica napus Seed Oil Accumulation and Chlorophyll Fluorescence Characteristics
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作者 Ruizhi Huang Huasheng Yu +7 位作者 Yong Yang Heqin Liu Xuelong Wu Zhihong Liu Haiyan He Gengwei Wu Wengjia Wang Hua Wang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第2期333-348,共16页
As global temperature rise,the threat of heat stress to rapeseed production is becoming more obvious.Exploring the response characteristics of two important biological pathways,oil accumulation and photosynthesis,to h... As global temperature rise,the threat of heat stress to rapeseed production is becoming more obvious.Exploring the response characteristics of two important biological pathways,oil accumulation and photosynthesis,to heat stress during B.napus seed filling is helpful in the genetic improvement of heat-tolerant rapeseed.The effects of heat stress on seed oil accumulation and chlorophyll fluorescence characteristics of 29 B.napus germplasms with different oil content and environmental sensitivity,including 6 rapeseed varieties which exhibited environmentsensitive/insensitive and with high,medium or low oil content,were tested by whole plant heat stress or the in vitro silique culture system.Both assay exhibited similar trend on oil content of the rapeseed germplasms.The heat effect on the chlorophyll fluorescence kinetic parameters F_(v)/F_(m),ETR and Y(Ⅱ)were also consistent.Heat stress significantly decreased oil content,although there was abundant genetic variation on heat tolerance among the genotypes.Correlation analysis showed that the decrease rate of F_(v)/F_(m) of silique heat-stressed B.napus developing seed was positive correlative to the decrease rate of mature seed oil content of the whole plant heat-stressed rapeseed(R=0.9214,P-value<0.01).Overall,the results indicated that heat stress inhibited oil accumulation and photosynthesis in B.napus developing seed.The decrease rate of chlorophyll fluorescence parameter F_(v)/F_(m) of heat-stressed developing seed could be used as the index of heat tolerant rapeseed identification.Further,two heat insensitive rapeseed varieties with high oil content were identified. 展开更多
关键词 Brassica napus L. heat stress seed filling stage oil accumulation chlorophyll fluorescence characteristics
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Fulfilling Meetings
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作者 JI JINGHU FAN 《ChinAfrica》 2023年第4期16-19,共4页
The annual Two Sessions highlight high-quality development The 14th National People’s Congress (NPC),China’s national legislature, concluded its first session on the morning of 13 March in Beijing,marking the comple... The annual Two Sessions highlight high-quality development The 14th National People’s Congress (NPC),China’s national legislature, concluded its first session on the morning of 13 March in Beijing,marking the completion of the annual sessions of the NPC and the National Committee of the Chinese People’s Political Consultative Conference (CPPCC), the top political advisory body,known collectively as Two Sessions. 展开更多
关键词 COLLECTIVE SESSION filling
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Grain-filling characteristics and yield differences of maize cultivars with contrasting nitrogen efficiencies 被引量:5
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作者 Qiang Li Lunjing Du +4 位作者 Dongju Feng Yun Ren Zhexin Li Fanlei Kong Jichao Yuan 《The Crop Journal》 SCIE CSCD 2020年第6期990-1001,共12页
To investigate the effect of nitrogen management on the grain-filling characteristics and yield formation of maize cultivars with contrasting nitrogen efficiencies,and to identify differences in grain-filling characte... To investigate the effect of nitrogen management on the grain-filling characteristics and yield formation of maize cultivars with contrasting nitrogen efficiencies,and to identify differences in grain-filling characteristics and yield of maize cultivars in response to nitrogen management,a two-year field experiment was conducted in southwest China in2015–2016.The grain-filling rate and duration of the N-inefficient cultivar XY 508 were higher than those of the N-efficient cultivar ZH 311.The 100-kernel weight of XY 508 was significantly higher than that of ZH 311.The kernel number per ear of ZH 311 was significantly higher than that of XY 508,making the population filling rate of ZH 311 significantly higher than that of XY 508.The higher population filling rate of the N-efficient maize cultivar led to a significant yield advantage over the N-inefficient maize cultivar.Nitrogen management effectively improved maize grain yield,but the response of maize cultivars with contrasting nitrogen efficiencies to nitrogen management was inconsistent.A basal fertilizer ratio 60.43%with a topdressing ratio 39.57%effectively increased grainfilling rate,delayed the time to maximum filling rate,prolonged the active filling period and effective grain-filling time,increased the 100-kernel weight,and maintained higher kernels per ear,thereby improving the population filling rate and maximizing the yield advantage of the N-efficient cultivar.A 100%basal fertilizer ratio not only increased the number of kernels per ear,but also maintained high grain filling characteristics to obtain a higher 100-kernel weight and increased the population filling rate,leading to a high grain yield in the N-inefficient cultivar.Thus,the 100%basal fertilizer ratio partially compensated for the deficient grain yield of the N-inefficient cultivar. 展开更多
关键词 MAIZE Grain filling Nitrogen management YIELD Population filling rate
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Peripheral arterial filling time and peripheral retina fluorescence features in ultra-widefield angiography
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作者 Hai-Cheng She Xi-Fang Zhang +2 位作者 Yong-Peng Zhang Xuan Jiao Hai-Ying Zhou 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第7期1034-1040,共7页
AIM:To evaluate the peripheral arterial filling time(PAFT)and venous filling time(VFT)in eyes without known diseases that may influence filling process using ultra-widefield(UWF)fluorescein angiography(FA),and to revi... AIM:To evaluate the peripheral arterial filling time(PAFT)and venous filling time(VFT)in eyes without known diseases that may influence filling process using ultra-widefield(UWF)fluorescein angiography(FA),and to review the peripheral retina fluorescence features.METHODS:A total of 30 eyes of 30 patients were retrospectively reviewed in this observational study.UWFFA was performed using Optos 200Tx.PAFT and VFT was recorded.The interval between the arterial or venous filling completion and the previous photo was documented.The appearance of the far peripheral retina was described as either granular background fluorescence or mottled fluorescent band or vascular leakage.Terminal vascular patterns was described as loop pattern or branching pattern.Microvascular abnormalities such as arteriovenous shunting,vessels crossing the horizontal raphe,right angle vessels,terminal networks,capillary nonperfusion,drusen or microaneurysms were evaluated.RESULTS:The normal limits of PAFT was 3.397-8.984s and 4.399-11.753s for VFT.The appearance of the far peripheral retina,defined as granular background(63%),mottled fluorescence(20%),or vascular leakage(17%),was symmetrical between both eyes.Capillary nonperfusion(23%)and microaneurysms(40%)were more frequently found in eyes with loop pattern than in eyes with branching pattern.Other peripheral signs such as right-angle vessels(73%),and terminal networks(80%)were commonly seen on UWF-FA in the normal peripheral retina.CONCLUSION:The main courses of retinal artery and vein filling time are overlapping with each other on UWF-FA.Notably,the arterial filling process is completed in the arteriovenous phase rather than the traditionally named arterial phase.There are various manifestations in the peripheral retina of normal eyes. 展开更多
关键词 peripheral arterial filling time venous filling time ultra-widefield fluorescein angiography peripheral retina fluorescence features
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一种基于红外成像障碍物检测的改进Flood Filling算法 被引量:1
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作者 段晓娟 史浩山 《传感技术学报》 CAS CSCD 北大核心 2009年第1期85-89,共5页
在对图像特征进行有效分割的基础上,提出了一种基于红外成像障碍物检测的改进Flood Filling算法,并首次将该算法应用到障碍物检测领域中。通过对模拟以及真实红外图像中目标的快速成功提取,不仅验证了该方法的有效性,同时实验结果也表... 在对图像特征进行有效分割的基础上,提出了一种基于红外成像障碍物检测的改进Flood Filling算法,并首次将该算法应用到障碍物检测领域中。通过对模拟以及真实红外图像中目标的快速成功提取,不仅验证了该方法的有效性,同时实验结果也表明了其较之原始算法对时效性的提高。 展开更多
关键词 图像处理 障碍物检测 FLOOD filling算法 红外图像
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Changes in Enzyme Activities Involved in Starch Synthesis and Hormone Concentrations in Superior and Inferior Spikelets and Their Association with Grain Filling of Super Rice 被引量:13
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作者 FU Jing XU Yun-ji +3 位作者 CHEN Lu YUAN Li-min WANG Zhi-qin YANG Jian-chang 《Rice science》 SCIE 2013年第2期120-128,共9页
The changes in activities of key enzymes involved in sucrose-to-starch conversion and concentrations of hormones in superior and inferior spikelets of super rice were investigated and their association with grain fill... The changes in activities of key enzymes involved in sucrose-to-starch conversion and concentrations of hormones in superior and inferior spikelets of super rice were investigated and their association with grain filling was analyzed.Four super rice cultivars,Liangyoupeijiu,IIyou 084,Huaidao 9 and Wujing 15,and two high-yielding and elite check cultivars,Shanyou 63 and Yangfujing 8,were used.The activities of sucrose synthase (SuSase),adenosine diphosphoglucose pyrophosphorylase (AGPase),starch synthase (StSase) and starch branching enzyme (SBE),and the concentrations of zeatin + zeatin riboside (Z + ZR),indole-3-acetic acid (IAA) and abscisic acid (ABA) in superior and inferior spikelets were determined during the grain filling period and their relationships with grain filling rate were analyzed.Maximum grain filling rate,the time reaching the maximum grain-filling rate,mean grain filling rate and brown rice weight for superior spikelets showed a slight difference between the super and check rice cultivars,but were significantly lower in the super rice than in the check rice for inferior spikelets.Changes of enzyme activities and hormone concentrations in grains exhibited single peak curves during the grain filling period.The peak values and the mean activities of SuSase,AGPase,StSase and SBE were lower in inferior spikelets than in superior ones,as well as the peak values and the mean concentrations of Z + ZR and IAA.However,the peak value and the mean concentration of ABA were significantly higher in inferior spikelets than in superior ones and greater in the super rice than in the check rice.The grain filling rate was positively and significantly correlated with the activities of SuSase,AGPase and StSase and the concentrations of Z + ZR and IAA.The results suggested that the low activities of SuSase,AGPase and StSase and the low concentrations of Z + ZR and IAA might be important physiological reasons for the slow grain filling rate and light grain weight of inferior spikelets in super rice. 展开更多
关键词 super rice superior SPIKELET INFERIOR SPIKELET enzyme activity hormone concentration grain filling
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HYDRODYNAMIC SIMULATION TO MOLD FILLING UNDER COUNTER GRAVITY 被引量:10
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作者 J.M. Zeng and Y.H. Zhou 1) Institute of Materials Science, Guangxi University, Nanning 530004, China 2) Department of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第2期780-783,共4页
In situ observations of the flow morphology during mold filling under counter gravity are conducted on a perspex water model by means of flow visualization, high speed photography and pattern processing. The experimen... In situ observations of the flow morphology during mold filling under counter gravity are conducted on a perspex water model by means of flow visualization, high speed photography and pattern processing. The experimental results indicate that influences of the dynamic factors on flow morphology can be expressed quantitatively with the parameterφ(k). The flow field takes on different morphology with change in values of φ(k). For thick and thin walled castings, the main dynamic factors influencing flow morphology are gravity and surface tension respectively. Under general circumstances, F_r and W_e should be equal in their values to guarantee the similarity between the prototype and the model in simulating mold filling under counter gravity by experiment. 展开更多
关键词 CASTING MOLD filling HYDRODYNAMICS
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High nitrogen application rate and planting density reduce wheat grain yield by reducing filling rate of inferior grain in middle spikelets 被引量:10
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作者 Yang Liu Yuncheng Liao Wenzhao Liu 《The Crop Journal》 SCIE CSCD 2021年第2期412-426,共15页
Excessive use of nitrogen fertilizer and high planting density reduce grain weight in wheat.However,the effects of high nitrogen and planting density on the filling of grain located in different positions of the wheat... Excessive use of nitrogen fertilizer and high planting density reduce grain weight in wheat.However,the effects of high nitrogen and planting density on the filling of grain located in different positions of the wheat spikelet are unknown.A two-year field experiment was conducted to investigate this question and the underlying mechanisms with respect to hormone and carbohydrate activity.Both high nitrogen application and planting density significantly increased spike density,while reducing kernel number per spike and 1000-kernel weight.However,the effects of high nitrogen and high plant density on kernel number per spike and 1000-kernel weight were different.The inhibitory effect of high nitrogen application and high planting density on kernel number per spike was achieved mainly by a reduction in kernel number per spikelet in the top and bottom spikelets.However,the decrease in 1000-kernel weight was contributed mainly by the reduced weight of grain in the middle spikelets.The grain-filling rate of inferior grain in the middle spikelets was significantly decreased under high nitrogen input and high planting density conditions,particularly during the early and middle grain-filling periods,leading to the suppression of grain filling and consequent decrease in grain weight.This effect resulted mainly from inhibited sucrose transport to and starch accumulation in inferior grain in the middle spikelets via reduction of the abscisic acid/ethylene ratio.This mechanism may explain how high nitrogen application and high planting density inhibit the grain filling of inferior wheat grain. 展开更多
关键词 Nitrogen Plant density WHEAT Grain filling Sucrose transport
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Study on Numerical Simulation of Mold Filling and Heat Transfer in Die Casting Process 被引量:17
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作者 Liangrong JIA, Shoumei XIONG and Baicheng LIU (Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第3期269-272,共4页
A 3-D mathematical model considering turbulence phenomena has been established based-on a computational fluid dynamics technique, so called 3-D SOLA-VOF (Solution Algorithm-Volume of Fluid), to simulate the fluid flow... A 3-D mathematical model considering turbulence phenomena has been established based-on a computational fluid dynamics technique, so called 3-D SOLA-VOF (Solution Algorithm-Volume of Fluid), to simulate the fluid flow of mold filling process of die casting. In addition, the math- ematical model for simulating the heat transfer in die casting process has also been established. The computation program has been developed by the authors with the finite difference method (FDM) recently. As verification. the mold filling process of a S-shaped die casting has been simulated and the simulation results coincide with that of the benchmark test. Finally, as a practical application, the gating design of a motorcycle component was modified by the mold filling simulation and the dies design of another motorcycle component was optimized by the heat transfer simulation. All the optimized designs were verified by the production practice. 展开更多
关键词 Study on Numerical Simulation of Mold filling and Heat Transfer in Die Casting Process MOLD SIMULATION
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Effects of nitrogen fertilizer and chemical regulation on spring maize lodging characteristics, grain filling and yield formation under high planting density in Heilongjiang Province, China 被引量:7
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作者 LIU Xiao-ming GU Wan-rong +2 位作者 LI Cong-feng LI Jing WEI Shi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第2期511-526,共16页
Now,lodging is a major constraint factor contributing to yield loss of maize (Zea mays L.) under high planting density.Chemical regulation and nitrogen fertilizer could effectively coordinate the relationship between ... Now,lodging is a major constraint factor contributing to yield loss of maize (Zea mays L.) under high planting density.Chemical regulation and nitrogen fertilizer could effectively coordinate the relationship between stem lodging and maize yield,which significantly reduce lodging and improve the grain yield.The purpose of this study was to explore the effects of chemical regulation and different nitrogen application rates on lodging characteristics,grain filling and yield of maize under high density.For this,we established a field study during 2017 and 2018 growing seasons,with three nitrogen levels of N100 (100 kg ha^(–1)),N200 (200 kg ha^(–1)) and N300 (300 kg ha^(–1)) at high planting density (90 000 plants ha^(–1)),and applied plant growth regulator (Yuhuangjin,the mixture of 3% DTA-6 and 27% ethephon) at the 7th leaf.The results showed that chemical control increased the activities of phenylalanine ammonia-lyase (PAL),tyrosine ammonia-lyase (TAL),4-coumarate:Co A ligase (4CL),and cinnamyl alcohol dehydrogenase (CAD),and increased the lignin,cellulose and hemicellulose contents at the bottom of the 3rd internode,which significantly reduced the lodging percentage.The lignin-related enzyme activities,lignin,cellulose and hemicellulose contents decreased with the increase of nitrogen fertilizer,which significantly increased the lodging percentage.The 200 kg ha^(–1) nitrogen application and chemical control increased the number,diameter,angle,volume,and dry weight of brace roots.The 200 kg ha^(–1) nitrogen application and chemical control significantly increased the activities of ADP-glucose pyrophosphorylase (AGPase),soluble starch synthase (SSS) and starch branching enzyme(SBE),which promoted the starch accumulation in grains.Additional,improved the maximum grain filling rate (V_(max)) and mean grain filling rate (V_(m)),which promoted the grain filling process,significantly increased grain weight and grain number per ear,thus increased the final yield. 展开更多
关键词 lodging resistance grain filling starch synthesis YIELD MAIZE
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Investigation of rheo-diecasting mold filling of semi-solid A380 aluminum alloy slurry 被引量:4
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作者 Zhi-yong Liu Wei-min Mao +2 位作者 Wei-pan Wang Zhi-kai Zheng Rui Yue 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第6期691-700,共10页
The rheo-diecasting mold filling capacity and the microstructure of the semi-solid A380 aluminum alloy slurry were investigated. The results show that the mold filling capacity was strengthened with increasing pouring... The rheo-diecasting mold filling capacity and the microstructure of the semi-solid A380 aluminum alloy slurry were investigated. The results show that the mold filling capacity was strengthened with increasing pouring temperature or increasing injection pressure. Under certain process parameters, the mold cavity was fully filled. However, the mold filling capacity decreased with increasing holding time. The mold filling capacity was improved with increasing shape factor of primary α(Al) grains; however, the solid fraction and the grain size significantly increased at the same time. In addition, the microstructures along the route of the spiral samples obviously differed. The grain size decreased gradually from the near-end to the far-end, whereas the shape factor increased gradually. 展开更多
关键词 aluminum alloys SEMI-SOLID SLURRY RHEO-DIECASTING MOLD filling microstructure
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Effects of shading after pollination on kernel filling and physicochemical quality traits of waxy maize 被引量:4
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作者 Huan Yang Yanling Shi +2 位作者 Renchao Xu Dalei Lu Weiping Lu 《The Crop Journal》 SCIE CAS CSCD 2016年第3期235-245,共11页
Understanding the effects of shading after pollination on kernel filling and physicochemical properties of waxy maize could improve kernel quality.Experiments were conducted to investigate the effects of shading(30% a... Understanding the effects of shading after pollination on kernel filling and physicochemical properties of waxy maize could improve kernel quality.Experiments were conducted to investigate the effects of shading(30% and 50% light deprivation,taken plants without shading as control) on kernel weight,size,and physicochemical properties during kernel development in 2013 and 2014 using two waxy maize varieties(Suyunuo 5 and Yunuo 7).Results indicated that shading reduced kernel filling rate and decreased kernel size and weight,and the influence was large under severe light deprivation conditions.The large reduction in kernel weight and volume of Suyunuo 5 in response to shading indicated that it was more sensitive to shading than Yunuo 7.Starch content was reduced and protein content was increased by shading,especially under severe shading after 22 days after pollination(DAP).The iodine binding capacity of Yunuo 7 was not affected by shading at fresh and maturity stages but was gradually decreased by shading at the newly formed stage,while the values for Suyunuo 5were decreased at 7 and 40 DAP only by moderate shading and were similar among three treatments at 22 DAP.Severe shading decreased crystallinity at all kernel development stages,whereas moderate shading decreased crystallinity at fresh stage and increased it at mature stage for Suyunuo 5.Crystallinity in Yunuo 7 was increased by shading at 7 DAP and decreased by shading at 40 DAP,whereas the value at 22 DAP was increased by moderate shading and reduced by severe shading,respectively.The average gelatinization temperatures at different stages were decreased by shading and showed no difference between two shading levels.The retrogradation percentage at 7 DAP for both varieties was increased by shading.The value at 22 DAP was increased by moderate shading for Suyunuo 5 and decreased by severe shading for Yunuo 7,respectively.The retrogradation percentage at 40 DAP was decreased by shading treatments for Suyunuo 5 and reduced only by moderate shading for Yunuo 7.Peak viscosity was decreased by shading at fresh stage for Yunuo 7 and at maturity for Suyunuo 5.In conclusion,shading after pollination inhibited kernel filling of waxy maize and reduced paste viscosity quality,but kernel retrograde quality,crystallinity and starch iodine binding capacity in response to shading were dependent on stage and variety. 展开更多
关键词 WAXY MAIZE SHADING KERNEL filling PHYSICOCHEMICAL property
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Study and Application of Mold Filling Simulation of Shaped Castings 被引量:5
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作者 Baicheng LIU Wei QIU +1 位作者 Houfa SHEN Zhiqiang GAO (Dept. of Mechanical Engineering, Tsinghua University Beijing 100084, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第2期107-112,共6页
In this paper, an algorithm for simulating fluid flow and heat transfer for mold filling of shaped castings is presented. The main features of the algorithm include: 1) a simple but practical technique based on VOF me... In this paper, an algorithm for simulating fluid flow and heat transfer for mold filling of shaped castings is presented. The main features of the algorithm include: 1) a simple but practical technique based on VOF method to determine free surface, 2) an explicit scheme of enthalpy to solve the energy equation more efficiently, and 3) an effective treatment to modify the flux deviation due to pressure iteration. In order to verify these methods, well controlled experiments have been repeatedly done with both water analog and gray iron pouring experiments to record the flow patterns and temperature variations. The calculated results are in accordance with the experimental ones. For the applications, the simulated initial temperature distribution right after mold filling was used to analyse subsequent solidification and to predict shrinkage defects.Actual castings were poured and tested in a foundry plant. The reuslts show that the defects predication with considering fluid flow effects is more precise than that without considering the effects. 展开更多
关键词 SIMULATION Study and Application of Mold filling Simulation of Shaped Castings MOLD
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There is plenty of space in the MXene layers: The confinement and fillings 被引量:3
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作者 Ming Lu Wenjuan Han +2 位作者 Haibo Li Wei Zhang Bingsen Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第9期344-363,I0011,共21页
MXenes have emerged as a new kind of 2D transition metal carbides,nitrides and carbonitrides.Origined from the unique 2D structure with a luxuriant combination of elements,MXenes drive a series of the investigations r... MXenes have emerged as a new kind of 2D transition metal carbides,nitrides and carbonitrides.Origined from the unique 2D structure with a luxuriant combination of elements,MXenes drive a series of the investigations related to energy storage and conversion,biometrics and sensing,lighting,purification and separation.For 2D layered MXene materials,the interspacing confined by the independent MXenes layers affords a distinct confinement space,which is similar to a nanoreactor that can be utilized for the storage of ions,nanoparticles,nanowires,and the materials with 2D or 3D structure.These fillings confined by MXene layers afford new opptunities for achieving improved properties and performance via complementary natural features,further the synergistic effect.Herein,we summarize the recent reports concerning with the confinded MXenes spacing and the fillings.The modification of interlayer distance lead by the intercalants were explored.We expect that our review may offer the route for a series of ongoing studies to address the MXenes. 展开更多
关键词 MXenes Interlayer distance INTERCALATION STRUCTURE fillings
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