Direct-binding quartz crystal microbalance immunosensor to detect carp metallothionein

Metallothionein (MT) is a valuable biomarker against xenobiotic heavy metal contamination in organs and blood of fish. In this study, MT was induced in carp blood by cadmium injection and was purified to homogeneity by DEAE-cellulose ion exchange column chromatography to be used dually as a standard and immunogen. A sensitive detection on carp MT was then followed using a batch-type direct-binding quartz crystal microbalance immunosensor system installed with a well cell. Among antibody immobilization methods tested, two methods that were carried out via a heterobifunctional thiolation cross-linker, and via the cross-linker and protein G showed their respective advantages in simplicity and sensitivity. When analyzed using the immunosensor for carp MT in the concentration range of 50-4000 ng/mL, the limit of detection around 250 ng/mL was obtained. Based on its reasonable sensitivity and real-time presentation for the sensor signal, the immunosensor of this study was presumed as a screening tool to monitor possible heavy metal contamination in a fish farm and imported fish.     

Quartz crystal microbalance studies on electrochemical behavior of electrodeposited Pd-Ni alloys

Electrochemical quartz crystal microbalance (EQCM) was applied in studies on electrochemical behaviour of Pd-rich Pd-Ni alloys in basic solutions. The results were compared with those obtained for pure Pd and Ni electrodes. The EQCM frequency response accompanying the desorption of the absorbed hydrogen is strongly influenced by the stresses generated during this process and depends on the alloy composition and the initial content of the absorbed hydrogen. The latter effect is much more pronounced for Pd-Ni alloys than for pure Pd electrode. The gravimmetric analysis of the oxidation processes of Ni(II) compounds on Pd-Ni electrodes and the subsequent reduction of the products is also complicated by the stresses accompanying these processes.     

Radiation-hardness studies of high OH content quartz fibres irradiated with 500 MeV electrons

We investigated the darkening of nine high OH⁻ fibre types irradiated with 500 MeV electrons from the Linac Injector of LEP (LIL) at CERN. The transmission of Xe light was measured in situ in the 350–800 nm range. The induced attenuation at 450 nm is typically 1.52±0.15 dB/m for a 100 Mrad absorbed dose. Two-parameter fits for darkening and recovery are presented. After irradiation the tensile strength remains essentially unchanged. For Polymicro quartz core fibres the tensile strength is typically 4.6±0.4 GPa.     

In-situ ellipsometry on sputtered dielectric and magneto-optic thin films

A four-gun magnetron sputtering chamber incorporating in-situ real-time spectroscopic ellipsometric analysis was used to grow magneto-optic memory structures. Data were taken at 44 wavelengths simultaneously from 410 nm to 750 nm, allowing the study of SiC/TbFeCo/SiC depositions on quartz in real time. These data were used to determine the sputter rates, optical constants, and the thicknesses of the films. The SiC data were taken at 1 min time intervals during growth, and the TbFeCo deposition was monitored continuously. Data were taken during the deposition of the entire structure without subjecting the sample to destructive analysis techniques or an oxidizing or reactive atmosphere.     

从某钽铌尾矿中回收长石和石英的试验研究

针对某钽铌尾矿中石英和长石含量较高的特点。在对矿样进行工艺矿物学分析基础上，制定了在碱性条件下，先脱杂质矿物。再浮云母。后浮长石和石英的综合回收工艺流程。试验得到的长石产品可达到玻璃及陶瓷Ⅱ级原料的质量标准，其矿物回收率约为70％～75％。石英产品可达到硅铁Ⅱ级及玻璃Ⅱ级原料的质量标准，其矿物回收率约为75％～80％。     

Application of synthetic fluid inclusions to simultaneous temperature–pressure logging in high-temperature (sub- to supercritical) geothermal systems

Batch-autoclave experiments have been conducted to evaluate the potential use of synthetic fluid inclusions as a simultaneous temperature–pressure (and fluid sampling) logging tool in deep-seated, high-temperature (>350 °C) geothermal systems. The application of synthetic fluid inclusions allows us to obtain information about thermal-pressure conditions in deep-seated geothermal systems, where conventional tools cannot be used because of the extreme temperature conditions. Fluid inclusions, up to 50 μm long, have been readily synthesized during 5-day autoclave experiments (conducted at 375–475 °C and 39–62 MPa) in pre-fractured, inclusion- and impurity-free artificial quartz. Inferred fluid inclusion (temperature–pressure) trapping conditions are calculated by deducing the intersection of isochores derived from microthermometric data for three sets of simultaneously trapped synthetic fluid inclusions in healed microfractures. Synthetic fluid inclusion logging offers a precise borehole temperature measurement technique without need of any pressure correction. Pressure estimates are less precise, although the method may be improved by using a combination of H₂O–NaCl and H₂O–KCl solutions/salinities, and fluid/quartz/amorphous silica systems that facilitate crack healing but trap fluids that do not homogenize at near-critical conditions.     

Micelle-assisted bilayer formation of cetyltrimethylammonium bromide thin films studied with combinatorial spectroscopic ellipsometry and quartz crystal microbalance techniques

We report on a combinatorial approach to study the formation of ultra-thin organic films using in-situ spectroscopic ellipsometry and quartz crystal microbalance methods. In contrast to the quartz crystal microbalance, which is sensitive to the total mass attached to the surface, including coupled and entrapped solvent, spectroscopic ellipsometry only measures the amount of adsorbent on the surface. By using these two techniques in tandem, we define and determine the solvent fraction of cetyltrimethylammonium bromide thin films adsorbed onto a gold-coated quartz crystal. Cetyltrimethylammonium bromide thin films grown from aqueous solutions above the critical micelle concentration reveal critical phases in thickness and porosity evolution. We relate these effects to the mechanisms of formation and removal and the structure of cetyltrimethylammonium bromide films, which we determine to have systemic defects due to the presence of micelles.     

Gemini型捕收剂对石英和磁铁矿的浮选性能

通过单矿物浮选试验,考察了Gemini型捕收剂Gemini-31503和十二胺对石英和磁铁矿的浮选特性,结果表明,Gemini-31503在较宽的pH范围里对石英具有很强的捕收能力,并且对石英具有良好的选择性,其性能明显优于十二胺。用Gemini-31503对石英和磁铁矿的人工混合矿进行反浮选,在不需再添加其他任何药剂的情况下取得了良好的分选指标。动电位测定和红外光谱分析结果显示,Gemini-31503在两种矿物表面的吸附主要为静电吸附,且在相同条件下,Gemini-31503在石英表面的吸附量比在磁铁矿表面的吸附量大。     

WFS往复式磁选机的研制及应用

针对强磁性矿物预选领域广泛应用的筒式磁选机磁场强度衰减大,磁场作用深度小,磁场不均匀且夹带严重等问题以及带式磁选机皮带表面磁场强度衰减大,皮带使用寿命较短且更换复杂费用高的问题研制了WFS往复式磁选机,介绍了WFS往复式磁选机的分选原理及技术特点。WFS1216往复式磁选机在广东某石英砂选厂进行工业应用,在给矿Fe_2O_3含量为0.065%的情况下,经过一次选别,取得的石英精砂含Fe_2O_30.042%,在精砂产率97.12%的情况下作业除铁率可达37.24%,有效去除了机械铁和强磁性矿物,避免了后续作业流程中强磁选机介质堵塞,设备运转平稳,故障率低。WFS往复式磁选机的研制为强磁性矿物预选领域增加了一种新型设备,在背景磁感应强度较高的情况下还可以用于弱磁性矿物的分选,具有广阔的市场应用前景。     

精密石英谐振式位移传感器

提出了用石英晶体谐振器构成的超精密位移或压力传感器的原理．由于石英晶体振荡器有超常的精度和稳定性，因而组成的位移或压力传感器也具有极高的精度和线性。还引入双晶振的差频原理，既消除了温度影响，又提高了频率变化范围，提高了测量分辨率。