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中国有色金属学会会刊：英文版 2000年第6期10卷 726-731页

作者：邓康任忠鸣蒋国昌上海大学上海

Coupling the quasi 3D numerical simulation of the electromagnetic field and the experiments with some metals, a series of phenomena in the processes of continuous casting with soft contacted mould was analyzed. Some theoretical and experimental models were presented, from which following results were obtained. 1) The electromagnetic force is related with electric conductivity of billet as a power function to 0.4. 2) The heat transfer between billet and mould is related with the contacting pressure, and it is a linear function for tin billet approximately. 3) The distance between initial solidification point and meniscus in billet is related with the surface magnetic flux density as a fourth root function. 4) The temperature gradient in the initial solidifying shell is reduced, which can decrease the tendency of hot tearing on the surface of billet, and increase the equiaxed crystal zone in billet. 5) The stronger the magnetic flux density is, the more shallow and the thinner the oscillation mark on the surface of billet is. 6) The depth of oscillation mark on the billet cast by the soft contacted mould can be reduced to about 10% in comparison with that on the billets cast by traditional mould. 7) In non dimensional condition, the average depth of the oscillation marks on the billets cast by the soft contacted mould decreases with increasing magnetic flux density on there as a complementary error function. [

关键词： electromagnetic continuous casting (EMC) soft contacted mould electromagnetic field (EMF)

The most economic cavity quantity in injection mould CAD based on concurrent engineering

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Journal of Harbin Institute of Technology(New Series) 2000年第1期7卷 30-34页

作者：轩景泉郎利辉康达昌朱宝泉 Dept. of Materials Engineering Jilin Institute of Technology Changchun 130031 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Dept. of Materials Engineering Inner Mongolia Polytechnic Institute Huhehaote 010062 China

Presents the conception of concurrent engineering employed for CAD/CAM of injection moulds by closely combining the management science with the manufacturing techniques with the cost of processing, material cost, etc taken into consideration from the conceptural design to delivery of products and concludes with the results of analyses that the cost of finished plastic parts is lower, the production efficiency is higher while energy is saved.

关键词： injection mould CAD concurrent engineering the most economic cavity quantity

Infiltration of mould from Crawl Space under the Prefabricated Bathroom

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Journal of Environmental Protection 2014年第10期5卷 914-921页

作者： Motoya Hayashi Haruki Osawa Kenichi Hasegawa Yoshinori Honma Hiromi Yamada Akita Prefectural University al Institute Yurihonjo Japan Department of Life Style and Space Design Miyagigakuin Women’s University Sendai Japan Iwate Prefectural University al Institute Morioka Japan Matsue College of Technology Matsue Japan National Institute of Public Health Wakou Japan

The indoor mould concentration depends not only on the outdoor mould source but also on the indoor mould source. The mould source is not only on the interior surface but also in the concealed spaces: a crawl space, a beam space, a wall cavity etc. Most detached houses in Japan have crawl spaces under the first floor. The humidity is high from spring to autumn in crawl spaces. Therefore the concentration of mould spore is very high in most crawl spaces. Prefabricated bathrooms called “bath-units” are installed in most Japanese houses. The authors showed in the previous studies that there are infiltration routes between bath-units and walls that the routes may lead chemical compounds from crawl space to indoor space. In this study, the influence of mould infiltration from crawl space upon indoor mould concentration is investigated using a test house which consists of a lavatory and a bathroom. The structure of the house is wooden post-and-beam. The house is airtight and insulated according to the latest building code for save energy. The mould concentrations were measured in the crawl space and the indoor spaces continuously using a mould multi-sampling system with a pump, valves and impingers. Before the measurements, the indoor mould concentration was made low using an air cleaner. The air flow rates were measured using tracer gases. After the exhaust fan was switched on, the mould concentration increased. The number of infiltrated mould was calculated using air flow rates and mould concentrations. The results showed that mould infiltration ratio may be one of the important indicators of indoor air quality.

关键词： mould Infiltration Air Tightness Crawl Space Tracer Gas

Indoor Exposure to mould and Dampness in Infancy and Its Association to Persistent Atopic Dermatitis in School Age: Results from the Greek ISAAC II Study

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Open Journal of Pediatrics 2016年第1期6卷 75-81页

作者： Papadopoulou Athina Mermiri Despina Xatziagorou Elpida Lambidi Stavroula Cratziou Christina Tsanakas Ioannis Allergy Pediatric Unit KAT General Hospital Athens Greece Allergology and Respiratory Unit Penteli’s Children Hospital Athens Greece 3rd Pediatric Department Aristoleleio University Thessaloniki Greece Evgenidio Hospital School of Medicine University of Athens Athens Greece

Introduction: The presence of mould as a source of perennial allergens and bacteria products has been related to the appearance of respiratory symptoms in several studies. Yet, its role in eczema has not been elucidated. The aim of this study was to investigate the association between exposure to indoor visible molds/dampness and the manifestation of eczema in children. Methods: The study is part of the Greek contribution to ISAAC IΙ that includes 2023 students of randomly selected public primary schools in Athens and Thessaloniki, aged 9 - 10 years old. The children represented a general population sample and were evaluated according to ISAAC II questionnaire, validated for Greek language. Additionally, skin prick tests to aero-allergens were performed and children were examined for active skin lesions. Results: 13% had suffered from eczema in the past, 9% had current and 2% had atopic eczema (positive at least one skin prick test). Out of the children examined, half reported that eczema first appeared after the age of five years old whereas 70% mentioned persistence of eczema. Dampness was reported in 10.8% and visible mould in 6.4% of all cases during infancy, while continued exposure until the age of 10 years old was reported in 38% and 33% out of them respectively. 10.8% of the sensitized children were positive to house dust mites and Alternaria, however, sensitization was not related to indoor exposure. In logistic regression analysis evaluating 20 environmental risk factors, a significant association was noted between the presence of indoor visible mold and dampness in infancy, and the presence of current eczema OR 1, 89 (95%CI 1.18 - 3.03). This association remained significant irrespective of the family history of eczema and sensitization. Conclusions: Frequently eczema first appears at early school age. The presence of visible mold and dampness at home during infancy appears to be an initial enhancing risk factor for the development but also for the persis

关键词： Persistent Atopic Dermatitis mould Dampness ISAAC II Children

Review on mould Contamination and Hygrothermal Effect in Indoor Environment

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Journal of Environmental Protection 2018年第2期9卷 100-110页

作者： Yuyan He Qinghai Luo Peihong Ge Guojie Chen Hanqing Wang School of Civil Engineering University of South China Hengyang China Engineering Lab of Hunan for the Technologies of Building Environment Control University of South China Hengyang China Key Lab of Hunan for the Technologies of Energy Conservation in Prefabricated Buildings University of South China Hengyang China

mould is an important factor which affects building environment and indoor air quality. Firstly, a variety of damages of mould contamination to human and building are reviewed. Then, the crucial factors of mould growth are analyzed;temperature and humidity are key factors. After that, the indoor mould growth models were analyzed. Heat and moisture transfer in building envelope is a key factor which affects mould growth environment;wall is sensitive to reach the critical condition which leads to mould growth and reproduction, results in contamination.

关键词： mould Contamination Building Environment mould Growth Model Heat and Moisture Transfer

Effects of several casting parameters on slag entrapment in mould( part A: water modeling)

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Baosteel Technical Research 2012年第3期6卷 32-38页

作者： ZHANG Feng MA Changsong LI Guangqiang Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China Silicon Steel Department Baoshan Iron&Steel Co.Ltd.Shanghai 201900China

The mechanism of slag entrapment in the mould was analyzed and the water modeling experiment was done according to the industrial manufacturing. The results show that the flow of the liquid steel becomes more active and the level fluctuation in the mould becomes bigger when the casting speed increases from 1.0 m/min to 1.2 m/min. So the control of slag entrapment in the mould becomes more difficult. When the depth of the nozzle increases from 30mm to 42. 5mm and the angle increases from 15~ downward to 30° downward, the level fluctuation in the mould becomes smaller and the slag entrapment in the mould also decreases. But the impact depth increases and the circumfluence vortex center moves downward, which is unfavorable for the flotation of gas bubbles and inclusions. Furthermore, the impact depth with side holes a （ 16.3 × 20mm2 ） and b （ 10 × 10 mm2 ） is almost equal, but a smaller level fluctuation can be obtained with side hole a.

关键词： casting parameter mould slag entrapment water modeling

Characterization of mould in Masonry in Hospital Environment—Case Study

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Open Journal of Civil Engineering 2016年第4期6卷 618-630页

作者： Washington Batista de Souza Adalberto Matoski Universidade Tecnológica Federal do Paraná Curitiba Brazil

The objective of this study is the characterization of mould inside and in the surface wall of a hospital. The present research was made on the wall of the Clinical Hospital of the Federal University of Paraná, Brazil. For the methodology the samples were extracted from the surface, mortar and brick. The samples were spread on Petri plates containing Sabouraud dextrose agar and incubated at 25℃ for seven days. The results of the 90 samples collected showed growth of 39% of colonies with the following distribution of microorganisms: Aspergillus (present in 27% of samples), Cladosporium, Absidia, Rhizopus, Rhodotorula, Fusarium, Penicillium and Aspergillus flavus. Within the investigated substrate, three species of different fungi were identified: Aspergillus flavus, Aspergillus fumigatus and Aspergillus niger.

关键词： Walls Brick mould Mortar Hospital

Effect of <i>Trichoderma harzianum</i>in Combination with Fungicides in Controlling Gray mould Disease (<i>Botrytis cinerea</i>) of Strawberry

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American Journal of Plant Sciences 2017年第4期8卷 651-665页

作者： Radwan M. Barakat Mohammad I. Al-Masri Plant Protection Research Center Faculty of Agriculture Hebron University Hebron Palestine

The effects of biofungicide formula containing the biocontrol agent Trichoderma harzianum (Jn14) as wettable powder in combination with the fungicides pyrimethanil and a mixture of cyprodinil and flydioxonil on Botrytis cinerea of strawberry in vitro, in vivo and in greenhouse were studied. The pathogen B. cinerea was more affected in vitro by low concentrations of the fungicides tested above 0.4 μg·ml-1 than the bioagent T. harzianum (Jn14). The later was almost insensitive to pyrimethanil. In the same direction, gray mould disease severity on strawberry detached leaves and whole plants was reduced up to 89% by the tested fungicides, compared to the control, while the application of T. harzianum (Jn14) alone reduced disease severity up to 45% on strawberry detached leaves, compared to the control. In the integrated control approach, the combination of T. harzianum (Jn14) with higher concentrations of the tested fungicides (ED50) completely inhibited strawberry gray mould disease severity in pots and the greenhouse.

关键词： Fungicides Trichoderma harzianum Botrytis cinerea Gray mould Strawberry

FRICTION COMPENSATION FOR AN HYDRAULIC CONTROL CONTINUOUS CASTING mould OSCILLATION SYSTEM

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FRICTION COMPENSATION FOR AN HYDRAULIC CONTROL CONTINUOUS CA...

Computer Simulation of mould Filling and Solidification of Castings

第四届流体传动国际会议

作者： Wu Xiaoming, Han Xiaojuan, Wang Yiqun Yanshan University, Post Code:066004, Qinhuangdao, China

Friction is one of the major limitations in performing high precision control. It affects both static and dynamic performance and causes instability when coupled to position or force feedback system. Thus, compensation for the friction between mold wall and strand shell has been one of the main research issues in a hydraulic servo control system used in continuous casting mould oscillation. This paper presents a dynamic model on the friction. The model has also been used to construct a friction observer and to perform friction compensation. Both frequency and time domain simulation results show that the control accuracy can reach to a high level by using friction compensation.

关键词： friction friction compensation continuous casting mould servocontrol

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Journal of Shanghai Jiaotong university(Science) 2000年第1期5卷 286-293页

作者： Zhian Xu WTCM Foundry Center, Research Center of the Belgian Metalworking Industry, 9052 Zwijnaarde, Belgium

A finite volume based 3-D computer code which can simulate fluid flow during mould filling coupled with heat transfer as well as solidification has been developed in WTCM Foundry Center. The code can predict cold shut during mould filling, shrinkage defects during solidification and aid designing the casting system. Several experiments of filling vertical plate castings have been carried out. A heat resistant glass window has been used to observe the liquid metal flow behavior. Although the plate casting has a very simple geometry, the associated flow behavior is quite complex. mould filling experiments carried out identical conditions never produce exactly the same results. The simulated results of the mould filling sequence and the temperature distribution have been compared with experiments. A good agreement has been achieved. The code has been used in foundries. A real application example is given which illustrates how to use computer simulation to aid designing the casting system. Sound castings based on computer aid designing have been produced. The process of designing castings by using simulation is completely different from the traditional way. The computer aided casting design offers the possibility to obtain a sound casting from the first time.

关键词： mould Filling Solidification Castings Simulation