Test of a prototype of the ZEUS backing calorimeter

We have studied the performance of a high resolution uranium-scintillator calorimeter followed by a much coarser backing calorimeter, made out of iron plates interleaved with planes of limited streamer tubes. The test results, obtained at the CERN-SPS hadron beam, show that the backing calorimeter can be used either to veto events with significant energy leakage from the uranium calorimeter or to correct for the energy. In both cases the energy resolution of the combined calorimeters improves significantly compared to the uranium calorimeter alone.     

An electromagnetic calorimeter with wavelength shifting fiber readout

We investigate the response of an electromagnetic calorimeter using wavelength shifting fibers for the readout. The calorimeter is a sandwich of lead and scintillator plates and the fibers are inserted into holes perpendicular to the plates. We study in particular light yield, uniformity of response and energy resolution. We also present a Monte Carlo interpretation of our experimental results.     

Fire resistance of inorganic sawdust biocomposite

The objective of this study was to manufacture fire-resistant biocomposite sandwich plates using waste sawdust as filler and an inorganic potassium aluminosilicate binder. Using binder contents of 29% and 34%, twelve biocomposite plates were fabricated without using any specialized equipment, heat, or pressure, thus producing an environmentally conscious biocomposite material. Several of the plates were strengthened with carbon and glass fiber reinforcements to create a more durable sandwich structure. The influence of binder content and reinforcement type on the heat release rate and smoke emission characteristics were investigated using the OSU heat calorimeter and the NBS smoke chamber, respectively. All specimens passed the Federal Aviation Administration requirements for heat release and smoke emission, the criteria used for evaluation of the test results in this study. Relative to 15 other wood plastic composites that utilize organic polymers, the inorganic biocomposite showed superior heat release rates during 5 min of fire exposure.     

Thermal conductivity of subcooled liquid oxygen

The thermal conductivity of liquid oxygen below 80 K and pressures up to 1 MPa has been measured using a horizontal, guarded, flat-plate calorimeter. The working equation of the calorimeter is based on the one-dimensional Fourier’s law. The gap between the calorimeter plates was measured in situ from a capacitance measurement. The cooling power to the calorimeter is provided by a two-stage Gifford-McMahan cryocooler. The absolute temperatures are measured using platinum resistance thermometers. The results are compared to existing data and analytical models.     

The sat calorimeter of the DELPHI experiment at LEP; results of a module test

The construction of an electromagnetic calorimeter using scintillating plastic fibres and lead plates is described. The calorimeter is part of the Small Angle Tagger (SAT) of the DELPHI experiment at the LEP collider, recording high-energy electrons, positrons and photons. Results from a test of a module of similar construction are presented. The module was found to have a linear energy response when exposed to electrons of 10–70 GeV, with an energy resolution given by σ/E[%] = (1.16² + (11.4/√E[GeV])²)^1/2.     

Bakelite RPCs for Digital Hadron Calorimeter

This paper presents the test results of Bakelite RPCs using readout pads with an area of 1 cm×1 cm and 1-bit resolution per pad (binary readout). The results include noise rate, detection efficiency and pad multiplicity as well as comparisons of different surface treatments for Bakelite plates. Pad multiplicity’s dependence on surface resistivity at the readout side is also reported. This study shows Bakelite RPCs can be used as the active elements of digital hadron calorimeter.     

Interactions of 200 GeV muons in an electromagnetic streamer tube calorimeter

We have investigated the response of an electromagnetic streamer tube calorimeter to 200 GeV muons. Muons undergo electromagnetic interactions in the absorber plates and produce electrons, photons or electron pairs the energy of which is measured by the calorimeter. Occasionally also catastrophic energy losses occur, so that in these very rare cases muons could even be misinterpreted as electrons.     

The ZEUS uranium-scintillator calorimeter for HERA

The high resolution calorimeter for the ZEUS detector at HERA is presented. The choice of a sandwich calorimeter from depleted uranium plates and plastic scintillator was made to accomplish compensation and thus the best possible energy resolution for hadrons and jets. The calorimeter is segmented transversely into towers and longitudinally into an electromagnetic and one or two hadronic sections. It is divided in a forward, barrel and rear part which surround hermetically the interaction region and the inner detectors. The expected energy resolutions are for electrons $\text{σ(E)}\text{E}\text{=}\text{0.15}\text{√E}$, and for hadrons $\text{σ(E)}\text{E}\text{=}\text{0.35}\text{√E}$, with a constant term of maximum 2% added in quadrature. First results from calorimeter test measurements are presented.     

An optical fiber readout for scintillator calorimeters

A method is described for collecting light from scintillation-counter calorimeters by means of an optical fiber connected to a wavelength shifter, covering an edge of a scintillator plate. The optical fiber passes between the continuous metallic plates and guides the light to a photomultiplier. The measurements with a prototype electromagnetic calorimeter give the energy resolution 8% (fwhm) at 26 GeV electron energy and uniformity across the surface of the calorimeter ±6%. The proposed method has a number of new advantages.     

An electromagnetic calorimeter with scintillator strips and wavelength shifter readout

We have built an electromagnetic calorimeter of the lead scintillator sandwich type. The dimensions of the lead plates are 20 × 60 cm² and their thickness 6 mm. A scintillator layer consists of 12 strips, 20 × 5 cm² and 2.5 mm thick. Each strip is read out using wavelength shifting plates at both sides. The mechanical stability of the module is provided by tie-rods and spacers. We have tested it in a 1 to 5 GeV electron beam. The influence of rods and spacers of various shapes and sizes on the uniformity of response and energy resolution is investigated.     

水热法制备Sb_2Te_3纳米线及其性能表征

在450K,pH值为11的条件下,以SbCl3,和Na2TeO3粉体为原料,用水热法制备了Sb2Te3纳米线。X-射线衍射(XRD)分析表明,所制的的材料为Sb2Te3,透射电镜(TEM)观察到Sb2Te3纳米线直径约为20nm,长度在200~600nm之间,并且自然平行密排成六边形纳米片状;然而在450K,pH值为13的条件下,制备出的产物则为完整的纳米片。扫描电镜(TEM)分析发现纳米线延(015)方向生长。差热测试得到Sb2Te3纳米线的熔点为727.5K。红外光谱的进一步研究表明,由Sb2Te3纳米线编织成的纳米片结构要优于整体生长成的纳米片,并就Sb2Te3纳米线的生长机理进行了初步推测。     

Hadron-Lepton cascade calculations (1–20 GeV) for a PbAl-lucite calorimeter

The results of Monte Carlo calculations for π^?(1–20 GeV) and e^?(1–10 GeV), normally incident on the center of a cylindrical calorimeter are presented. The calorimeter design has 60 unit cells of alternating PbAlLucite plates and is a simplified model of one to be used at the Stanford Linear Accelerator Center. General characteristics of the total and spatial energy deposition are given. Pulse height spectra, as well as spectra of the transverse fractional energy distributions and of their first and second moments, are given to aid in hadron-lepton discrimination. Sampling fluctuations are also examined for this purpose. Some results for the effects of a uniform probability of incidence over the central transverse strip and also some longitudinal discriminants are presented.     

硅油对EVA/ATH复合材料的协同阻燃作用

采用氧指数、锥形量热仪等手段,研究了羟基硅油（HSO）在乙烯-醋酸乙烯酯（EVA）/氢氧化铝（ATH）体系中的协效阻燃作用。氧指数结果表明,随着HSO添加量的增加,复合材料的氧指数略有所下降,样品EVA1～EVA5的氧指数从31下降至27.5。锥形量热仪结果表明,随着HSO添加量的增加,复合材料的热释放速率峰值呈明显的...     

A liquid argon calorimeter prototype for forward region at the LHC

We report on the design and on beam test results of a liquid argon calorimeter prototype. This technology was proposed as an option for the forward region of an experiment at the future Large Hadron Collider (LHC) at CERN. The measurements were performed using electrons from the ITEP PS with an energy range of 1 to 5 GeV.     

Fibre mortar composites under fire conditions: effects of ageing and moisture content of specimens

Two small scale test series were performed using the cone calorimeter heating method to detect any differences in the way various fibres affect the thermal properties of a standard mortar. The cone shaped heater of the cone calorimeter produces a uniform heat flux on the sample surface over an area of 100×100 mm². The heat flux was adjusted to 50 kW m^?2, which corresponds to the early stage of a fully developed fire. The total exposure also corresponds roughly to the ISO 834 time-temperature curve during the first 30 minutes. Short ageing of the specimens gave very clear differences in thermal properties between fibre mortars. However, no such differences were observed with oven dried samples. This shows the importance of carrying out tests in conditions as close as possible to the end use conditions of the material or product.     

UL94与聚合物三种燃烧实验的相关性

包括UL94实验在内的一些聚合物燃烧实验被广泛用于评价火灾危害和阻燃性能,但同一产品的UL94等级与其他燃烧实验得出的阻燃级别有时相差较大。文中综述了UL94等级与锥形量热仪、微型量热仪和氧指数实验结果的关联关系,论述其间存在的关联性的理论基础及影响关联程度高低的因素,并建议对UL94实验条件、不稳定燃烧过程和滴落行为作深入细致的研究,以便更好地理解UL94实验与其它实验之间的异同。     

5052铝合金金字塔型点阵夹芯板的成型及其组织性能研究

采用冲压成型的5052铝合金板作为金字塔点阵芯层,2024铝合金作为面板,以Zn-Cd-Ag-Cu为钎料,分别在430℃、460℃进行炉中钎焊。观察焊后钎料及夹芯板的焊接接头组织,并进行显微硬度测试和压缩试验。结果表明,5052金字塔型点阵夹芯板在430℃焊接具有良好的组织和性能。     

Material characterization of laminated composite plates via static testing

A minimization method for material characterization of laminated composite plates using static test results is presented. Mechanical responses such as strains and displacements are measured from the static tests of the laminated composite plates. The finite element method is used to analyse the deformation of the laminated composite plates. An error function is established to measure the differences between the experimental and theoretical mechanical responses of the laminated composite plates. The identification of the material elastic constants of the laminated composite plates is formulated as a constrained minimization problem in which the elastic constants are determined by making the error function a global minimum. A number of examples are given to illustrate the feasibility and applications of the proposed method.     

Mechanical performance of heat/fire damaged novel flame retardant glass-reinforced epoxy composites

Novel glass-reinforced epoxy composites containing a phosphate-based intumescent and inherently flame retardant (cellulosic (Visil, Sateri) and phenol-formaldehyde (Kynol)) fibres have been fabricated. These components are added both as additives in pulverized form and as fibre interdispersed with intumescent as a fabric scrim for partial replacement of glass fibre. Fire testing has been performed using a cone calorimeter at an incident heat flux of 50 kW/m² and the results have shown that introduction of the intumescent/FR fibre to the matrix can significantly reduce the peak heat release values and smoke intensities evolved by composites. Mechanical testing in tensile and flexural modes of these samples has shown that inclusion of the intumescent/fibre system does not adversely influence their tensile and flexural properties. The effect of heat on mechanical properties has been observed by heating the samples in a furnace at 400 °C for 5 min and tested for their flexural and tensile strength retentions. The charred samples remaining after cone exposure were also tested for stiffness test. Some of the samples retained up to 21% of the initial stiffness after being exposed to high heat flux in the cone calorimeter whereas, the control sample was rendered unusable after cone calorimeter exposure.