VIMP中结构拐角对纤维预成型体渗透特性的影响

采用真空导入模塑工艺(VIMP)制备纤维增强聚合物基复合材料多墙结构件时,多墙体拐角处的纤维弯曲变形可能导致多墙体局部渗透特性发生变化。通过可视化流动实验考察了拐角对多墙体渗透特性和树脂流动行为的影响。结果表明:无论是否使用导流介质,多墙体中的拐角对树脂流体在VIMP灌注过程中都具有局部阻力作用,降低了树脂充模流动速度和多墙体整体表观渗透率,即存在拐角效应;拐角处铺放导流介质能有效降低拐角效应;随着拐角到注胶口的距离增大,整体表观渗透率表现为先下降后上升。     

高等级住宅外墙外保温应用技术

为降低建筑采暖和空调制冷的能耗,贵都花园外墙采用外保温,介绍了墙体外保温用材、施工程序及操作工艺,竣工后通过热工性能检测,取得了明显的节能效果,并获安徽省“省级科技示范工程”称号。     

羟基磷酸铜钙催化环已烷氧化脱氢反应研究

采用共沉淀法制备羟基磷酸铜钙（CCHP）,考察了CCHP催化剂在环已烷气相氧化脱氢反应中的催化性能。结果表明,该类催化剂只表现出深度脱氢活性,在所考察的温度范围内,催化剂活性和稳定性较好。催化剂进一步用正硅酸乙酯处理后,其表面变得更亲油,脱氢活性明显改善,600 ℃时,环已烷脱氢产物苯的收率可达25.6%。     

Determination of the multiplication of leakage neutrons and the fissile material mass in deeply subcritical systems

The previously developed analysis of measurements of neutron multiplication in deeply subcritical states of multiplying media by the α-Rossi method (method of double neutron-neutron coincidences) is supplemented by a new analysis of triple coincidences. To obtain the neutron multiplication and the effective neutron multiplication coefficient, it is no longer necessary to know the intensity of the source of spontaneous fissions – it is determined from experiments. This makes it possible to determine simultaneously the mass and enrichment of a fissile substance placed in a container. Measurements are performed and analyzed using uranium and plutonium blocks and fast-neutron detectors as well as AWCC (active well coincidence counters) neutron detectors. Previous measurements performed using the coincidence counters are analyzed. It is shown that without calibration of the ²⁴⁰Pu and ²³⁹Pu mass by measurement of counting rate of single neutrons as well as double and triple coincidences in ordinary experiments the error (1σ) in determining the mass fraction of ²⁴⁰Pu in plutonium is 0.3–0.8% and the error for all plutonium is 3–12%.     

Preparation and Characterization of Red Luminescent Ca_(0.8)Zn_(0.2)TiO_3∶ Pr~(3+), Na~+ Nanophosphor

Pr dopedalkalineearthmetaltitanateswithper ovskitestructurehaverecentlybeenthesubjectof manyinvestigations.Thisisbecauseoftheirhigh chemicalstability,strongandsharpredemission,and longafterglowluminescence[1～13].CaTiO3∶Pr3+,asa relativelynewluminescencematerialofthatcategory,andexhibitsredcathodoluminescencelocatedatthe CIEcoordinate[8]ofx=0.680andy=0.311,very closeto“idealred”ofNTSC(NationalTelevision StandardsCommittee).Inaddition,itisapromising redlongpersistencephosphor,whichmayp…     

碳酸盐前驱体和CS_2硫化制备SrY_2S_4∶Eu~(2+)红色荧光粉及其表征

以Sr2+,Y3+和Eu3+的混合硝酸盐溶液为阳离子溶液,以(NH4)2CO3为沉淀剂,共沉淀法制备了碳酸盐前驱体,TG-DSC分析结果表明,随着(NH4)2CO3浓度的升高,前驱体组成由碱式碳酸盐向正盐转变。以CS2为硫化剂,高温煅烧前驱体合成了SrY2S4∶Eu2+红色荧光粉。XRD表明前驱体经800℃处理得到纯相SrY2S4。荧光光谱和SEM研究表明在[Sr(NO3)2+Eu(NO3)3]∶[Y(NO3)3]∶[(NH4)2CO3]=0.25∶0.50∶2.00(摩尔比)条件下制备前驱体,然后1050℃煅烧4 h所得荧光粉的发光强度最大,粒径小于1μm,粒子形貌呈椭球。Eu2+在SrY2S4基质中的最佳掺杂摩尔分数是0.6%。     

河北夏杖子金矿床的同位素地质研究

采用质谱分析等方法,测试了夏枚子金矿床石英流体包裹体和金属硫化物的同位素组成,获得石英流体包裹体Rb-Sr等时线年龄为105.4±7.2Ma;锶同位素初始比值为0.7126±0.0001;氢同位素组成δD‰为-91.7～-73.1;氧同位素组成δ~(18)OH_2O‰为5.68～6.23;金属硫化物的硫同位素组成δ~(34)S‰=-23.38～-14.52;铅同位素组成~(206)Pb/~(204)Pb=16.441～16.615,~(207)Pb/~(204)Pb=15.228～15.256,~(208)Pb/~(204)Pb=36.268～36.356。矿床成矿作用发生于燕山晚期,成矿热液主要为岩浆热液,金矿成矿物质来源于硅铝壳中下部太古代结晶基底,矿床成因是与燕山期岩浆热液有关的中—低温热液脉状金矿床。     

冶金企业实施CIMS总体方案的探讨——天津市轧三制钢有限公司CIM总体方案简介

对连续过程工业实施CIMS总体技术方案作了较为深入的探讨,并对天津市轧三制钢有限公司实施CIMS总体方案及技术路线进行了详细介绍。     

ILC for non-minimum phase system

In this paper we propose a design method of an iterative learning controller (ILC) for a non-minimum phase (NMP) system by model-matching theory. The ILC consists of two learning filters acting on both the previous input signal and the previous error signal. To design the learning filters, we convert the convergence condition of the ILC into the model-matching problem and get the stable and proper learning filter by solving the Nevanlinna's algorithm. To show the usefulness of the proposed algorithm, some design examples are included.