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Effect of Rice Bran Quality and Protein Supplement, Base Mix, and/or Soybean Meal on Growing Pig Performance in Cambodia
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作者 Chenda En Sath Keo +4 位作者 Jessie L. Vipham Bunna Chea Kroesna Kang Michael D. Tokach Joel M. DeRouchey 《Open Journal of Animal Sciences》 2020年第4期714-724,共11页
The objective of this study was to evaluate the effect of rice bran quality and dietary supplement source on growing pig performance. A total of 60 castrated male pigs (Yorkshire × Duroc, initially 16.1 kg) were ... The objective of this study was to evaluate the effect of rice bran quality and dietary supplement source on growing pig performance. A total of 60 castrated male pigs (Yorkshire × Duroc, initially 16.1 kg) were used for 52-day trial. Pigs were allotted to pens in a completely randomized design (4 pigs per pen) and assigned to four dietary treatments in a 2 × 2 factorial with factors being rice bran source (high or low-quality) and source of protein, vitamins, and minerals (supplement or soybean meal and base mix). Analyzed protein and fat level for the high- and low-quality rice bran was 11.07% and 5.86% and 11.20% and 4.50%, respectively. Crude fiber content for high- and low-quality rice bran was 13.44% and 27.79%. Diets were formulated in two phases (phase 1: 16 to 27 and phase 2: 27 to 48 kg) to adjust to the pig’s nutrient requirements. There was no evidence for an interaction (P > 0.05) between rice bran quality × supplement type or main effect of supplement type (soybean meal + base mix vs protein supplement) for final body weight, average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (F/G). However, pigs fed high-quality rice bran had improved (P < 0.001) ADG and F/G and lower ADFI compared to pigs fed low protein rice bran. In conclusion, rice bran quality as measured by protein, crude fiber, and fat influenced growing pig performance, while the type of dietary protein supplement did not. Additionally, rice bran with high protein, fat, and low fiber improved ADG and F/G. 展开更多
关键词 base mix PIGS Protein Supplement Rice Bran Soybean Meal
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Effect of Dietary Supplement, Base Mix, and/or Soybean Meal on Growing Pig Performance
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作者 Samorn Sreng Sath Keo +5 位作者 J. M. DeRouchey M. D. Tokach Bunna Chea Kroesna Kang Lyda Hok J. L. Vipham 《Open Journal of Animal Sciences》 2020年第3期535-544,共10页
A total of 60 crossbred pigs (Yorkshire × Duroc, initially 56.5 kg) were used in a 42-day trial to evaluate the effect of replacing a commercial high protein supplement with soybean meal and/or a base mix in rice... A total of 60 crossbred pigs (Yorkshire × Duroc, initially 56.5 kg) were used in a 42-day trial to evaluate the effect of replacing a commercial high protein supplement with soybean meal and/or a base mix in rice bran-based diets on pig growth performance. Pigs were allotted to pens by body weight and pens were randomly assigned to dietary treatments in completely randomized design. There were 4 dietary treatments with 3 or 4 replicate pens per treatment and 4 pigs per pen. Dietary treatments were: 1) 80% rice bran with 20% high protein supplement (RBS20), 2) 95% rice bran with 5% high protein supplement (RBS5), 3) 97.5% rice bran with 2.5% base mix (RBB2.5), and 4) 92.5% rice bran with 5% soybean meal and 2.5% base mix (RBSBB). The base mix included vitamins, macro and trace minerals, L-Lysine, L-Threonine, and DL-Methionine. Overall (d 0 to 42) average daily gain was greater (P < 0.001) for pigs fed RBSBB and RBS20 diets than pigs fed the RBS5 or RBB2.5 diets. Pigs fed the RBS5 diet had reduced (P < 0.004) average daily feed intake compared to all other treatments. Similarly, feed efficiency (feed/gain) was improved (P < 0.004) for pigs fed RBSBB and RBS20 diets compared with pigs fed RBS5 or RBB2.5. For economics, income over feed cost was the greatest (P < 0.01) for the diet containing soybean meal and base mix compared to pigs fed the RBS20 diet, SBS5, and RBB2.5. In conclusion, feeding pigs a rice bran diet with base mix and soybean meal had similar growth performance and increased economic return compared to feeding a rice bran diet with high protein supplement. Use of soybean meal and base mix provides an opportunity for increased economic return for pig farmers. 展开更多
关键词 base mix Growing Pigs Growth Performance Rice Bran Soybean Meal
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Effect of SiO2 Micropowder Addition on Properties of Alumina-magnesia Based Wet Gunning Mix for Working Layer
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作者 SHEN Mingke WEI Guoping +1 位作者 XUE Junzhu HE Bo 《China's Refractories》 CAS 2017年第4期12-16,共5页
The magnesia - alumina based wet gunning mix was prepared using tabular corundum aggregates,fused mag- nesia aggregates, tabular corundum micropowder, silica mieropowder and pure calcium ahuninate cement as the main s... The magnesia - alumina based wet gunning mix was prepared using tabular corundum aggregates,fused mag- nesia aggregates, tabular corundum micropowder, silica mieropowder and pure calcium ahuninate cement as the main starting materials. Effects of silica micropowder ad- ditions (0, 0. 2% , 0. 5% , 1.0% , 1.5% , 2. 0% , and 2.5%, by mass, the same hewinafier) on properties oJ the gunning mix were researched. The results show that when ttze silica micropowder addition is i. 0% -2. 0% , the gunning mix has good .flou,ability and pumpability. Adding 2.5% silica micropowder, the nepheline forms at 1 600 ℃, which will reduce the high. temperature proper- ties of ntagnesia -ahtmina wet gunning mix. The intro- duction qf silica micropowder has obvious effects on cold mechanical properties of the gunning mix. For the speci- tnens dried at 110 ℃ , the strength increases slightly with the silica micropowder addition increasing. For the specimens heat-treated at 1 600 ℃ for 3 h, the strength in- creases nutrkedlv with the silica micropowder addition in- creasing. When keeping the water addition and particle size di, stribution constant, the residual linear expansion rate qf the specimen with 1.5% of silica micropowder is the lowest, ltot modulus tf rupture at 1 450 ℃ .for 0. 5 h oJ the specimens decreases gradually with the increase of silica fame addition. A small amount of silica micropow- der is beneficial for the slag penetration resistance. 展开更多
关键词 silica micropowder alumina- magnesia based wet gunning mix slag resistance
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A Mixed Host Emitting Interlayer Based on CBP:TPBi in Green Phosphorescent Organic Light-Emitting Diodes
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作者 徐瑶 张雨亭 +2 位作者 寇志起 程爽 卜胜利 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第4期147-150,共4页
A series of green phosphorescent organic light-emitting diodes based on bipolar-transporting material 4,4Lbis- (carbazol-9-yl) biphenyl (CBP) are prepared. We insert a mixed host emitting interlayer (CBPx: elect... A series of green phosphorescent organic light-emitting diodes based on bipolar-transporting material 4,4Lbis- (carbazol-9-yl) biphenyl (CBP) are prepared. We insert a mixed host emitting interlayer (CBPx: electron- transporting material 1,3,&tris (N-phenylbenzimidazole-2yl) (TPBi)1-X) in the middle of the emitting layer, and the best performance appears when x is 2/3. The position of this interlayer can also affect the performanee of phosphorescent organic light-emitting diodes. When this interlayer is close to the side of the electron transporting layer, the maximum value of luminance, the current efficiency and the power efficiency are 34090cd/m2 at 12 V, 60. 6 cd/A and 56.6 lm/W, respectively. 展开更多
关键词 of is EML OLEDs A mixed Host Emitting Interlayer based on CBP:TPBi in Green Phosphorescent Organic Light-Emitting Diodes in CBP on
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Nonlinear mixed-effects height to crown base and crown length dynamic models using the branch mortality technique for a Korean larch( Larix olgensis ) plantations in northeast China 被引量:8
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作者 Weiwei Jia Dongsheng Chen 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期2095-2109,共15页
Korean larch(Larix olgensis)is one of the main tree species for aff orestation and timber production in northeast China.However,its timber quality and growth ability are largely infl uenced by crown size,structure and... Korean larch(Larix olgensis)is one of the main tree species for aff orestation and timber production in northeast China.However,its timber quality and growth ability are largely infl uenced by crown size,structure and shape.The majority of crown models are static models based on tree size and stand characteristics from temporary sample plots,but crown dynamic models has seldom been constructed.Therefore,this study aimed to develop height to crown base(HCB)and crown length(CL)dynamic models using the branch mortality technique for a Korean larch plantation.The nonlinear mixed-eff ects model with random eff ects,variance functions and correlation structures,was used to build HCB and CL dynamic models.The data were obtained from 95 sample trees of 19 plots in Meng JiaGang forest farm in Northeast China.The results showed that HCB progressively increases as tree age,tree height growth(HT growth)and diameter at breast height growth(DBH growth).The CL was increased with tree age in 20 years ago,and subsequently stabilized.HT growth,DBH growth stand basal area(BAS)and crown competition factor(CCF)signifi cantly infl uenced HCB and CL.The HCB was positively correlated with BAS,HT growth and DBH growth,but negatively correlated with CCF.The CL was positively correlated with BAS and CCF,but negatively correlated with DBH growth.Model fi tting and validation confi rmed that the mixed-eff ects model considering the stand and tree level random eff ects was accurate and reliable for predicting the HCB and CL dynamics.However,the models involving adding variance functions and time series correlation structure could not completely remove heterogeneity and autocorrelation,and the fi tting precision of the models was reduced.Therefore,from the point of view of application,we should take care to avoid setting up over-complex models.The HCB and CL dynamic models in our study may also be incorporated into stand growth and yield model systems in China. 展开更多
关键词 Larix olgensis plantation Height to CROWN base CROWN LENGTH Branch MORTALITY technique NONLINEAR mixed-eff ects models
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Pressure-Dependent Base-Wavefunction Admixture and Lifetime of R1 State of La3Lu2Ga3O12:Cr3+
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作者 ZHANG Zheng-Jie MA Dong-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1147-1152,共6页
作为导致压力依赖者 R_1-line-shift 颠倒andR_1状态一生的一个关键因素,在 10 K ,混合度 of|t_2~2 (~ 3T_1 )的压力依赖者变化 e~4T_2 >并且|t_2~( 32 ) E >在 R_1 州的 ofLLGG 的波浪功能的 base-wavefunctions :Cr~(3+)被... 作为导致压力依赖者 R_1-line-shift 颠倒andR_1状态一生的一个关键因素,在 10 K ,混合度 of|t_2~2 (~ 3T_1 )的压力依赖者变化 e~4T_2 >并且|t_2~( 32 ) E >在 R_1 州的 ofLLGG 的波浪功能的 base-wavefunctions :Cr~(3+)被计算了并且分析。从这, thepressure 依赖的 R_1-line-shift 颠倒的物理起源被揭示了。而且,由使用| t_2~2 (~ 3T_1 )的所有方形的混合系数的和的thepressure依赖的价值 e~4T_2 >在 R_1 状态的波浪功能, LLGG 的 R_1 状态的一生:在各种各样的压力的Cr~(3+)被计算了,它在对观察结果的好同意。在t_2~( 32 )之间的量反十字路口效果 e~4T_2 由于两个纺纱轨道的相互作用andelectron声子相互作用铺平的 E 和 t_2~2 (~ 3T_1 )是显著的,它与| t_2~2 (~ 3T_1 )的混合有关 e~4T_2 >并且|t_2~( 32 ) E >象低高度的 crystal-Reid 转变一样。 展开更多
关键词 高压效应 基态波函数 R1态寿命 量子反交叉 晶体场
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Catalytic Synthesis of Polymethyl Methacrylate by Mixed Ligand Schiff Base Lanthanocene Complexes
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作者 Yousaf MUHAMMAD 1, HUANG Jiling 1, FENG Zuofeng 1, QIAN Yanlong 1, SUN Junquan 2, PAN Zhida 2(1 Laboratory of Organometallic Chemistry, East China University of Science and Technology, Shanghai 200237, China 2 Material and Chemical Engineering Co 《催化学报》 CSCD 北大核心 2000年第4期293-294,共2页
关键词 聚甲基丙烯酸甲酯 催化合成 席夫碱稀土茂配合物
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高掺量磷石膏道路基层材料配比设计及性能研究
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作者 黄绪泉 吴钦楠 +2 位作者 赵小蓉 董江峰 李茜 《金属矿山》 CAS 北大核心 2024年第3期296-302,共7页
按传统矿质混合料设计掺磷石膏道路基层材料难以大规模消纳磷石膏,为实现磷石膏在道路基层材料中大规模利用,通过骨料替代法进行高掺量磷石膏道路基层材料配比设计,确定适宜的碎石比(5~10 mm粒级与10~25 mm粒级质量比39∶61)后以不同掺... 按传统矿质混合料设计掺磷石膏道路基层材料难以大规模消纳磷石膏,为实现磷石膏在道路基层材料中大规模利用,通过骨料替代法进行高掺量磷石膏道路基层材料配比设计,确定适宜的碎石比(5~10 mm粒级与10~25 mm粒级质量比39∶61)后以不同掺量替代磷石膏基胶凝材料体系,再击实然后得出最佳含水率及最大干密度。通过对设计好的配比进行性能试验筛选,得出适宜配比为P85S60,养护28 d的试件抗压强度最大达5.39 MPa,体积变化率较低,且养护7 d后试件的体积增长稳定,体积变化率最终维持在0.5%左右,有利于现场道路施工应用。所有配比浸出氟、磷均满足《污水综合排放标准》(GB 8978—1996)一级限值,相较于常规水泥稳定碎石材料,该道路基层材料浸出液的酸碱性不会额外增加不利影响。通过XRD和SEM分析可知,胶凝材料水化产生的钙矾石和水化硅酸钙包裹在未反应的二水石膏周围,另外针棒状钙矾石和水化硅酸钙填充微小孔隙,使得试件整体结构密实、强度增加、体积稳定性增强。 展开更多
关键词 道路基层材料 配比设计 性能试验 磷石膏 抗压强度 体积变化率
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工业场地铊、砷污染土壤修复技术研究
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作者 阎丽 范翘 陈冬素 《中国锰业》 2024年第3期108-112,共5页
研究开发了一种工业场地铊和砷污染土壤修复技术。采用常见的氯化钾、氯化锰、氢氧化钾、膨胀珍珠岩和磷石膏,经过等温等离子体处理等一系列化学反应,制备了一种铁锰基混合粉的修复药剂,该药剂制备过程简单且具有强氧化性和强吸附性。... 研究开发了一种工业场地铊和砷污染土壤修复技术。采用常见的氯化钾、氯化锰、氢氧化钾、膨胀珍珠岩和磷石膏,经过等温等离子体处理等一系列化学反应,制备了一种铁锰基混合粉的修复药剂,该药剂制备过程简单且具有强氧化性和强吸附性。实验结果表明,在修复时间为7 d,修复药剂中氯化锰与氯化铁物质的量比为3∶10,膨胀珍珠岩粉末与氯化铁锰固液比为25∶100,磷石膏与铁锰基混合粉质量比为3∶10的条件下,处理污染土壤,铊、砷的稳定效率分别达到99.21%和99.68%。此外,通过BCR法对土壤中铊、砷的形态分析显示,修复后土壤中铊、砷主要以残渣态存在,显著降低了其对环境的潜在危害。本研究为工业场地重金属污染土壤的修复提供了一种高效、环保的解决方案。 展开更多
关键词 土壤修复 铁锰基混合粉 BCR法
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基于BOPPPS线上线下混合式案例教学模式的中医诊断学教学探索 被引量:2
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作者 吴凡 李泽庚 +6 位作者 董昌武 周雪梅 赵建根 汪莉 李玲秀 吴传云 徐慧 《中国中医药现代远程教育》 2024年第3期21-24,共4页
在分析中医院校中医诊断学课程定位及当前教学中存在的突出问题后,作者基于BOPPPS教学模型,创新性地将线上线下教学与案例教学相融合,采取课前线上线下教学、课中线下教学、课后线上师生交流和线下学生深入实践探寻问题相结合的模式,对... 在分析中医院校中医诊断学课程定位及当前教学中存在的突出问题后,作者基于BOPPPS教学模型,创新性地将线上线下教学与案例教学相融合,采取课前线上线下教学、课中线下教学、课后线上师生交流和线下学生深入实践探寻问题相结合的模式,对提高学生学习积极性和学习效果进行探索。经初步实践证实,该教学模式能够激发学生的学习积极性与主动性,进一步提高学生的主体意识和自学能力,提高其四诊技能的综合运用能力和临床思辨能力,有效提高教学质量。因此,在中医诊断学课程教学中,基于BOPPPS教学模型的线上线下混合式案例教学模式为改善当前传统教学模式的不足提供了一种新的思路,值得研究及推广。 展开更多
关键词 中医诊断学 BOPPPS 线上线下混合式教学 案例教学 教学改革
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“项目式”与“混合式”教学方法相结合在仪器分析实验课的教学改革与实践
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作者 张平 高祥 +3 位作者 裴文霞 汪建飞 周毅 赵建荣 《广东化工》 CAS 2024年第7期187-189,共3页
传统的“观摩式”教学以教师为中心,缺乏师生互动,加之实验课考核力度不够,学生实践能力得不到充分锻炼,存在的问题日益突出。为了能够培养适应市场需求的应用型人才,我们采用了“项目式”和“混合式”教学方法相结合的方式,重新构建实... 传统的“观摩式”教学以教师为中心,缺乏师生互动,加之实验课考核力度不够,学生实践能力得不到充分锻炼,存在的问题日益突出。为了能够培养适应市场需求的应用型人才,我们采用了“项目式”和“混合式”教学方法相结合的方式,重新构建实验课程考核评价体系,两种教学模式相得益彰,以学生为中心,有助于培养学生实践技能、分析与解决问题的能力。 展开更多
关键词 “项目式”教学法 “混合式”教学法 仪器分析实验 教学改革 实践
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新工科建设背景下线上线下混合式教学提升产出导向课程目标达成度的优势及教学设计案例——以“果蔬贮藏加工学”为例
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作者 杨杨 苏琳 +1 位作者 韩育梅 张美莉 《农产品加工》 2024年第7期122-125,共4页
新工科建设背景下的高等工科教育对专业课的高阶性、创新性和挑战度提出了新的要求,传统课堂教学遭遇瓶颈。线上线下混合式教学基于课程目标开展反向教学设计,将线上自主学习和线下课堂教学进行有机的深度融合,聚焦高阶能力的培养,是提... 新工科建设背景下的高等工科教育对专业课的高阶性、创新性和挑战度提出了新的要求,传统课堂教学遭遇瓶颈。线上线下混合式教学基于课程目标开展反向教学设计,将线上自主学习和线下课堂教学进行有机的深度融合,聚焦高阶能力的培养,是提高专业课程教学质量和课程目标达成度的有效途径。以“果蔬贮藏加工学”为例阐述了开展混合式教学改革的必要性,并展示了混合式教学设计的案例。 展开更多
关键词 新工科 产出导向 混合式教学 果蔬贮藏加工学 教学设计
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PBL混合式教学模式在“内科护理学”教学中的应用
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作者 赵莉萍 《淮北职业技术学院学报》 2024年第1期59-63,共5页
为探讨PBL混合式教学模式在内科护理学教学的应用效果,选择104名护理专业学生作为研究对象,分为对照组和观察组。观察组采用基于问题的教学方法(PBL),结合线上线下混合式教学模式,对照组采用传统式教学模式,对比两组的期末成绩和学生自... 为探讨PBL混合式教学模式在内科护理学教学的应用效果,选择104名护理专业学生作为研究对象,分为对照组和观察组。观察组采用基于问题的教学方法(PBL),结合线上线下混合式教学模式,对照组采用传统式教学模式,对比两组的期末成绩和学生自评学习效果。研究发现,观察组学生的期末成绩和对学习效果的认同程度明显高于对照组学生(P<0.05),PBL混合式教学模式有助于提高内科护理学的教学质量和学习效果。 展开更多
关键词 基于问题的教学方法(PBL) 混合式教学 内科护理学 教学改革
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Evaluation and Optimization of the Mixed Redundancy Strategy in Cloud-Based Systems
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作者 Pan He Xueliang Zhao +2 位作者 Chun Tan Zhihao Zheng Yue Yuan 《China Communications》 SCIE CSCD 2016年第9期237-248,共12页
Mixed redundancy strategies are generally used in cloud-based systems,with different node switch mechanisms from traditional fault-tolerant strategies.Existing studies often concentrate on optimizing a single strategy... Mixed redundancy strategies are generally used in cloud-based systems,with different node switch mechanisms from traditional fault-tolerant strategies.Existing studies often concentrate on optimizing a single strategy in cloud computing environment and ignore the impact of mixed redundancy strategies.Therefore,a model is proposed to evaluate and optimize the reliability and performance of cloud-based degraded systems subject to a mixed active and cold standby redundancy strategy.In this strategy,node switching is triggered by a continual monitoring and detection mechanism when active nodes fail.To evaluate the transient availability and the expected job completion rate of systems with such kind of strategy,a continuous-time Markov chain model is built on the state transition process and a numerical method is used to solve the model.To choose the optimal redundancy for the mixed strategy under system constraints,a greedy search algorithm is proposed after sensitivity analysis.Illustrative examples were presented to explain the process of calculating the transient probability of each system state and in turn,the availability and performance of the whole system.It was shown that the near-optimal redundancy solution could be obtained using the optimizationmethod.The comparison with optimization of the traditional mixed redundancy strategy proved that the system behavior was different using different kinds of mixed strategies and less redundancy was assigned for the new type of mixed strategy under the same system constraint. 展开更多
关键词 冗余优化 计算系统 混合策略 评估 马尔可夫链模型 主动节点 切换机制 灵敏度分析
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混合钎料对镍基单晶高温合金大间隙钎焊接头组织和性能的影响
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作者 贺彤 王诗洋 +2 位作者 李可馨 侯星宇 孙元 《焊接》 2024年第6期1-8,共8页
【目的】采用一种新型镍基钎料和母材成分一致的高熔点合金粉混合的方法制备出混合钎料,研究了添加的高熔点合金粉的粒径和配比对钎缝微观组织和力学性能的影响。【方法】采用扫描电子显微镜对钎焊接头的析出相、元素分布、微观组织进... 【目的】采用一种新型镍基钎料和母材成分一致的高熔点合金粉混合的方法制备出混合钎料,研究了添加的高熔点合金粉的粒径和配比对钎缝微观组织和力学性能的影响。【方法】采用扫描电子显微镜对钎焊接头的析出相、元素分布、微观组织进行了分析,并对钎焊接头的硬度及持久性能进行了测试。【结果】研究表明,接头主要由钎料合金区(FAZ)、界面连接区(IBZ)和扩散影响区(DAZ)三部分组成。钎料合金区主要由M3B2和M8B型硼化物及γ/γ′相组成。界面连接区由γ和γ′沉淀强化相组成。当合金粉粒径为44μm和75μm时,均可得到无缺陷的焊接接头;但当合金粉粒径尺寸达177μm时,钎缝内会形成孔洞缺陷。【结论】随着合金粉比例的提高,接头连接区的显微硬度有所上升。当合金配比由30%到50%,接头的持久寿命由15 h增加至34 h;但进一步提升比例至60%时,接头的持久寿命下降至0.6 h。该文的结果可为实现高温热端零部件的连接和修复工程应用提供理论依据和参考价值。 展开更多
关键词 镍基单晶高温合金 混合粉末钎料 大间隙钎焊 持久性能
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微孔白云石加入量对镁钙质中间包干式料性能的影响
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作者 孟佳泽 陈定 +2 位作者 顾华志 黄奥 付绿平 《耐火材料》 CAS 北大核心 2024年第1期68-71,共4页
以白云石为原料,采用二步煅烧法制备的致密镁钙砂是镁钙质中间包干式料常用的耐火原料。然而二步煅烧法工艺复杂,资源耗费大,且致密镁钙砂不利于中间包干式料隔热性能的提升。以一步煅烧法(1400℃保温3 h)制备的微孔白云石和电熔镁砂为... 以白云石为原料,采用二步煅烧法制备的致密镁钙砂是镁钙质中间包干式料常用的耐火原料。然而二步煅烧法工艺复杂,资源耗费大,且致密镁钙砂不利于中间包干式料隔热性能的提升。以一步煅烧法(1400℃保温3 h)制备的微孔白云石和电熔镁砂为主要原料,分别于1100、1550℃热处理后制备了镁钙质干式料试样,研究了微孔白云石加入量(质量分数分别为0、15%、30%、45%和60%)对试样性能的影响。结果表明:随着微孔白云石加入量的增加,1100℃热处理后试样的线收缩率和体积密度呈减小趋势,常温耐压强度先增大后减小;1550℃热处理后试样的线收缩率先减小后显著增大,显气孔率增加,热导率大幅降低,但常温耐压强度和抗渣性能降低。当微孔白云石加入量为60%(w)时,1550℃热处理后试样在800℃下的热导率为2.410 W·m^(-1)·K^(-1),与传统镁质干式料相比下降了51.9%,同时常温耐压强度为26.0 MPa,在力学性能略微降低的情况下表现出优异的隔热性能。 展开更多
关键词 镁钙质 中间包 干式料 白云石 隔热性能
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基于OBE理念的发电厂电气部分课程建设
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作者 孙丽颖 白锐 赵凤贤 《高教学刊》 2024年第2期71-74,共4页
发电厂电气部分是电气工程及其自动化专业重要的专业课程,对学生工程实践能力的培养起到重要的支撑作用。该文基于成果导向教育理念(OBE),建立MOOC教学平台的“课前-课中-课后”线上线下混合式闭环教学模式,构建丰富的教学资源,课程教... 发电厂电气部分是电气工程及其自动化专业重要的专业课程,对学生工程实践能力的培养起到重要的支撑作用。该文基于成果导向教育理念(OBE),建立MOOC教学平台的“课前-课中-课后”线上线下混合式闭环教学模式,构建丰富的教学资源,课程教学目标支撑毕业要求,构建成果导向的课程考核评价体系,体现以学生学习为中心。在新的教学模式下,学生学习效果明显改善。在OBE理念指导下,通过MOOC平台进行电气类专业课程改革是改进教学方法、提升教学质量的有效手段,也是未来教学改革的方向。 展开更多
关键词 成果导向教育 一流课程 线上线下混合式教学 发电厂电气部分 课程建设
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双层SiO_(2)宽谱带减反射涂层的制备及性能表征
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作者 赵昊森 肖志葳 +2 位作者 王逸翔 贾红宝 朱世海 《大学物理实验》 2024年第3期27-32,共6页
采用无模板溶胶-凝胶法,成功制备在可见光范围内具有高透射率和良好疏水性的宽谱带减反射双层SiO_(2)涂层。采用提拉法在石英基底上沉积SiO_(2)双层涂层,底层和顶层的折射率分别为1.34和1.15。其中,底层由酸催化和碱催化混合SiO_(2)溶... 采用无模板溶胶-凝胶法,成功制备在可见光范围内具有高透射率和良好疏水性的宽谱带减反射双层SiO_(2)涂层。采用提拉法在石英基底上沉积SiO_(2)双层涂层,底层和顶层的折射率分别为1.34和1.15。其中,底层由酸催化和碱催化混合SiO_(2)溶胶制备得到,顶层薄膜的溶胶是使用六甲基二硅氮烷(HMDS)作为改性剂,制备得到三甲基硅烷化的SiO_(2)纳米粒子体系。根据优化膜系设计要求,选择合适工艺参数镀制双层涂层,测试结果显示,SiO_(2)双层涂层在可见光区的平均透射率为98.64%,静态水接触角可达134°。 展开更多
关键词 溶胶-凝胶法 酸碱混合SiO_(2)溶胶 减反射薄膜 表面有机改性
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多源声发射信号混合重叠组稀疏分类研究
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作者 邓韬 刘哲潮 +1 位作者 汪华章 何磊 《计量学报》 CSCD 北大核心 2024年第1期64-72,共9页
针对高速列车车体裂纹声发射检测的多源、波模式重叠及噪声干扰问题,提出一种基于本征模态的混合重叠组稀疏(MOGS)分类方法用于声发射源识别。MOGS是一种兼顾组间和组内稀疏,同时允许类间特征重叠的结构稀疏模型。设计了一种新的噪声预... 针对高速列车车体裂纹声发射检测的多源、波模式重叠及噪声干扰问题,提出一种基于本征模态的混合重叠组稀疏(MOGS)分类方法用于声发射源识别。MOGS是一种兼顾组间和组内稀疏,同时允许类间特征重叠的结构稀疏模型。设计了一种新的噪声预分解矩阵以降低本征模态分解计算量,选取目标特征频带模态为分类样本来提高类间差异。通过K-SVD层次稀疏组套索罚训练MOGS类别字典,并给出一种罚函数块坐标可分离的近似光滑处理过程以实现MOGS套索求解。实验表明,该方法对几类多源含噪信号分类准确率均高于80%,在识别率和波形重构效果上优于对比方法。 展开更多
关键词 声学计量 声发射 组稀疏分类 混合重叠组稀疏 多源信号识别
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湿热环境下低吸水率玻化微珠保温砂浆配合比研究
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作者 崔双双 郭晓慧 +1 位作者 罗天凤 王旭 《福建理工大学学报》 CAS 2024年第3期213-218,共6页
为解决东南沿海地区显著的风驱雨(WDR)现象易引起的建筑外墙渗水、墙体材料劣化等问题,通过两阶段共14组配合比试验,配制了一种低吸水率的外墙玻化微珠水泥基材料,研究了其在湿热环境下累计吸水量与吸水后导热系数的变化规律。研究结果... 为解决东南沿海地区显著的风驱雨(WDR)现象易引起的建筑外墙渗水、墙体材料劣化等问题,通过两阶段共14组配合比试验,配制了一种低吸水率的外墙玻化微珠水泥基材料,研究了其在湿热环境下累计吸水量与吸水后导热系数的变化规律。研究结果表明:与混凝土相比,玻化微珠水泥基材料可以显著降低材料的导热系数、吸水量,热工性能优异,玻化微珠保温砌块可以有效提高砌块的热工性能,但也会降低材料抗压强度。与混凝土相比,玻化微珠水泥基材料的导热系数、7 d累计吸水量和吸水7 d后导热系数分别为0.336 W/(m·K)、185.8 g和0.483 W/(m·K),分别是混凝土的26.4%、62.4%和30.1%,吸水7 d后导热系数增大0.147W/(m·K),增幅为混凝土的44.3%。 展开更多
关键词 湿热环境 低吸水率 玻化微珠水泥基材料 配合比试验
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