Study of Cosmic Ray Impact on Planck/HFI Low Temperature Detectors

Once that the focal plane of the HFI instrument of the Planck mission (launched in May 2009) has reached operational temperature, we have observed the thermal effect of cosmic ray interaction with the Planck satellite, located at Lagrangian point L2. When a particle hits a component of the bolometers (e.g.: thermometer, grid or wafer) composing the focal plane of HFI, a thermal spike (called glitch), due to deposited energy, is observed. Processing these data revealed another effect due to high energy cosmic ray particle showers: High Coincidence Events (HCE), composed of glitches occurring coincidentally in many detectors and with a temperature increase from nK to \(\upmu \) K after the shower. A flux of about 100 HCE per hour has been calculated. Two types of HCE have been detected: fast and slow. For the first type, the untouched bolometers reach the same temperature as the touched ones in a few seconds which can be explained by a storage of the deposited energy in the stainless steel focal plane. The second type of HCE is not fully understood yet. These effects might be explained by extra conduction from the helium released from cryogenic surfaces, creating a temporary thermal link between the different stages of the HFI.     

超微颗粒的性能表征

从粒度测量、团聚态表征以及氧化和水解程度评价其 3方面总结了超微颗粒的性能和表征方法。     

Electrodeposition and Characterization of Co Particles on Ultrathin Polypyrrole Films

Ultrathin polypyrrole (PPy) films with the thicknesses of 20, 50, and 100 nm were prepared by electropolymerization. Co particles with a charge density in the range of 125–1,250 mC cm^?2 were grown on these ultrathin PPy films. Current time transients were used to investigate the electrochemical properties. It was observed that the deposition of Co becomes more difficult as the PPy film gets thicker. The chemical structure of PPy films in the reduced and oxidized forms and a PPy film with Co particles were examined with Fourier transform infrared spectroscopy (FTIR). The characteristic peaks of the oxidized PPy film were observed. The intensity and position of some peaks changed, and new peaks appeared for the reduced PPy film, possibly as a result of undoping of the PPy film. There are further differences in the spectrum of Co on PPy. The morphology of the films was studied by scanning electron microscopy (SEM). It was found that the morphology was affected by both the PPy film thickness and the Co charge density. Magnetic measurements were made by vibrating sample magnetometry (VSM). The magnetic moment of the samples increases with both decreasing PPy film thickness and increasing charge density due to increased Co deposition. For all samples, the easy axis is parallel to the film plane.     

肺功能仪校准规范的编制说明

肺功能仪校准规范已通过全国物理化学委员会的技术审查,为便于该校准规范的使用者准确掌握实施标准条款的具体要求和规定,本文主要就该校准规范制订的任务来源、目的意义等方面进行简要介绍,并对该校准规范的主要条款进行阐述及补充说明.     

Aerosol Synthesis and Characterization of Ultrafine Fullerene Particles

Aerosol routes were used to produce fullerene particles in the nanometer size range. Particle formation mechanisms at processing temperatures of 400-700°C were studied by measuring particle number and mass size distributions in the gas phase by a differential mobility analyzer and a low-pressure impactor respectively. Subsequently, the foils of the impactor onto which fullerene particles were collected were examined by HPLC.     

聚甲基丙烯酸甲酯-羰基铁复合粒子的制备及其表征

采用原位分散聚合法制备聚甲基丙烯酸甲酯-羰基铁复合粒子，研究了复合粒子粒径、形貌、磁流变液的沉降稳定性和流变学性能。结果表明，复合粒子呈近似球形，平均粒径为9μm，密度为1.49g/mL；核壳比为3：2，正常工作温度范围内，复合粒子具有热稳定性；复合粒子磁流变液的沉降稳定性得到了改善；流变学性能有一定的下降。     

碳酸铅纳米粉体的制备及其表征

在溶液结晶体系中加入适当的添加剂可改变晶体的生长环境,影响晶体的生长、团聚行为,从而得到理想的晶形及晶粒尺寸。本研究在化学沉淀法制备碳酸铅的反应体系中加入适量表面活性剂,通过表面活性剂对晶粒生长和团聚的抑制作用,制备了疏松的碳酸铅纳米粉体。XRD和TEM分析表明,反应体系中加入表面活性剂后,制备的碳酸铅纳米粉体的晶形发生了改变,纳米碳酸铅颗粒呈球形,粒度均匀,为60 nm左右。     

聚苯胺-聚乙二醇导电共聚物粒子的制备与表征

以盐酸为掺杂剂,通过氧化共聚法制备了聚苯胺(PAn)-g-聚乙二醇(PEG)共聚物粒子,用红外光谱、透射电镜对粒子的结构进行了表征,并对共聚物粒子的热稳定性、导电性能进行了测试。结果表明,PAn-g-PEG共聚物粒子具有很好的热稳定性,且经过LiClO4掺杂后兼具离子-电子导电性能,当n[Li+]/n[EO]=0.1时,共聚物粒子的导电率最大。     

KNO3/GO复合含能材料的制备与表征?

分别采用重结晶法、中和法和溶剂-非溶剂法制备了硝酸钾/氧化石墨烯(KNO3/GO)复合含能材料。通过负载前后质量的变化对KNO3的负载量进行比较,并运用X射线衍射能谱(XRD)、傅里叶红外光谱(FTIR)、场发射扫描电镜(FESEM)和热重/差热分析(TG/DTA)对复合材料进行了表征。结果表明:3种方法中,KNO3都能均匀地负载在GO片层表面,溶剂-非溶剂法中KNO3的负载量最大;重结晶法制备的复合含能材料的反应快速且剧烈,反应起始温度较GO提前了74℃;中和法制备的材料的反应相对平缓,经历了3个阶段;溶剂-非溶剂法的热分解过程基本和纯KNO3相同。     

水热法制备二氧化锡纳米微粒及其表征

通过水热法,使五水四氯化锡在氨水的环境中合成纳米级的二氧化锡微粒。采用冷冻干燥法得到粉体。使用XRD对实验合成的产物进行一系列的分析,结果发现所得的二氧化锡粉体基本为四方晶系（即金红石型）。纳米二氧化锡微粒有近球形,棒状,椭球形等的形貌,其粒径范围从4nm到120nm。本实验主要研究以下几个因素对二氧化锡粉体形貌的影响：溶液的浓度、合成温度、合成时间及溶液pH值。     

Aerosol Synthesis and Characterization of Ultrafine Fullerene Particles

Abstract

Aerosol routes were used to produce fullerene particles in the nanometer size range. Particle formation mechanisms at processing temperatures of 400-700°C were studied by measuring particle number and mass size distributions in the gas phase by a differential mobility analyzer and a low-pressure impactor respectively. Subsequently, the foils of the impactor onto which fullerene particles were collected were examined by HPLC.     

粉煤灰微珠-TiO_2复合颗粒制备与性能表征

以粉煤灰微珠为基体,利用TiOSO_4水解法,制备TiO_2包覆微珠复合颗拉。通过扫描电镜、X射线衍射、比表面积、超声振荡和光电子能谱等检测手段,对复合微珠的表面形貌、包覆层相组成、比表面积、包覆层与基体结合强度与结合方式进行了研究和探讨。检测与分析表明:得到的复合微珠表面包覆层为均匀非连续包覆,包覆层主要为金红石相,包覆后微珠比表面积比未包覆前提高了超过600倍,且包覆层颗粒与基体结合强度较高,二者间存在化学键的联结。     

基于隐性需求的产品信息表征设计解读

目的以隐性需求为核心针对产品信息进行研究,从表征设计角度进行信息设计。方法通过表征性形式设计、内容设计,探讨隐性需求产品信息的显性设计方法,并从表征性效用设计探讨隐性与显性需求及对应的设计方法的转换和平衡。结论尝试在产品设计初始即强调顾客的潜在需求与感知,避免产品信息盲目设计导致内容丢失,实现隐性需求产品信息的显性传达,更能以此引导产品、信息的交互发展以及产品设计未来发展方向。     

Fracture Characterization of High-Density Polyethylene Materials Using the Energetic Criterias

Impact behavior of polymers has received considerable attention in recent years, and much work based on fracture mechanic approaches has been carried out. In this paper, fracture behavior in large deformation of a high density polyethylene (HDPE) materials was investigated through experimental impact testing on single edge notched specimen (SENB) and by using theoretical and analytical fracture criteria concepts. Moreover, a review of the main fracture criteria is given in order to characterize the toughness of this polymer in the both cases (static and dynamic). The fractured specimens obtained from the Charpy impact test were characterized with respect to their fracture surfaces. Characteristic zones of the fracture surface can be assigned to different stages and mechanisms of the fracture process. Finally, for a better understanding of fracture and damage mechanisms and to provide the best estimation of fracture toughness in impact, an experimental approach based on microscopic observations (SEM) was used.     

Characterization and identification of rejection mechanisms in nanofiltration membranes using extended Nernst–Planck model

Nanofiltration (NF) membranes have found increasing applications especially in water and wastewater treatment. In order to predict and optimize the performance of NF membranes, the membranes need to be characterized properly in terms of their structural parameters such as pore radius (r _p) and effective thickness (Δx/A _k) as well as the effective charge density (X _d). In this work, three cellulose acetate NF membranes were fabricated to different properties and were characterized using a model based on the extended Nernst–Planck equation. The results show that the variations of r _p, Δx/A _k and X _d are quite distinct between the three membranes. The membranes were found to have r _p>1.2 nm and high X _d. Thus the rejection mechanism depends very much on the Donnan effect rather than the steric effect. The high rejection of several negatively charged organics and salts confirmed this finding. Apart from being effective, this method of characterization offers a cheaper alternative in understanding NF membranes. Electronic Publication     

粉体及其改性颗粒微观结构的透射电镜表征

介绍了一种适用性很广的材料微观结构表征法.应用该技术可以从粉体及其改性颗粒试样中切取可供透射电镜研究的薄膜,对微观结构进行表征.制样的效率高,薄膜的薄区大,完整性好.对材料微观结构的透射电镜和高分辨电镜表征具有重要意义.     

TiO2包覆石墨颗粒的制备及表征

以钛酸四丁酯，二乙醇胺，无水乙醇和水为主要原料，采用溶胶－凝胶技术在石墨颗粒表面包覆了TiO2，研究了复合颗粒制备的条件，表面形貌和特性，获得了金红石相TiO2完全包覆石墨的复合颗粒。     

1-取代的4-硝基咪唑含能衍生物的合成、表征及热分解性能?

以4-硝基咪唑为原料,通过与2-氨基-3,5-二硝基-6-氯吡啶、2,6-二氯-3-硝基吡啶缩合,合成出未见文献报道的化合物6-(4-硝基-咪唑-1-基)-2-氨基-3,5-二硝基吡啶(1#)及6-氯-3-硝基-2-(4-硝基-咪唑-1-基)-吡啶(3#),收率分别为65%、52%;并采用此种方法优化了3-硝基-2-(4-硝基-咪唑-1-基)-吡啶(2#)的合成,收率为85%。进一步尝试了化合物3#的叠氮化反应,得到5-叠氮基-6-硝基四唑基[1,5-a]吡啶(4#)。采用核磁共振、质谱、红外光谱、元素分析等方法对相关化合物的结构进行了表征。利用TG和DSC分析法研究了化合物1#的热行为,结果表明:化合物1#的初始分解温度为221.83℃,分解放热总量为302.65 k J/mol,热失重温度范围为209.17~398.67℃,累计热失重71.84%。     

铁氮化合物吸收剂的制备及其微波吸收特性的研究

采用固气反应法制备铁氮化合物吸收剂,研究了工艺参数对产物组成、微波电磁参数的影响,既而确定产物中形成较高比例Fe4N的条件.结果表明:在360℃,3h反应条件下,产物中Fe4N质量分数最高,为45%;反应时间不变,产物介电常数随反应温度升高而增加,磁导率则相反;反应温度不变,产物磁导率随反应时间的增加而降低;产物经分散处理后制得的吸波材料反射率优于处理前,在11.67GHz处,可达-11.18dB.     

反相微乳液法制备纳米羟基磷灰石及其表征

采用水溶液(W)/环己烷(O)/Triton X-100(S)/正戊醇(A)反相微乳液体系制备出粒径为20～60nm的球状羟基磷灰石(Hap)颗粒,并用TEM、XRD、IR和动态激光散射等手段对合成的样品进行形貌和结构表征.研究结果表明,合成的Hap具有弱结晶性,与人骨结构较相似.改变水油比可实现对纳米Hap颗粒尺寸的控制.微乳液经超声处理后,可制得尺寸为80nm×(5～15)nm的Hap纳米针状晶体.增加Hap微乳液的搅拌时间对纳米Hap的颗粒度、粒度分布影响不大.