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71.
GAO Shi MA Qingjie CUI Qu LIU Lin ZHOU Xueyan JIA Bing CHEN Zuowei ZHANG Haishan 《核技术(英文版)》2013,(2):36-40
The 99mTc-3PRGD2 targeted SPECT/CT scanning was of significance in detecting differentiated glioma.In this work,the diagnostic value of 99mTc-3PRGD2 scintigraphy in brain glioma was evaluated by the ten clinically verified brain glioma patients after obtaining informed consent.The patients first accepted X-ray imaging to localize the detecting regions before administrating with 99mTc-3PRGD2 at a mean radioactivity of 849±115 MBq via single intravenous bolus injection 2 h prior to SPECT/CT imaging.Tumor samples for detectingαvβ3 were collected by surgical operations two weeks after the scintigraphy.The results of CT and SPECT scanning were merged and compared.The correlation between tumor occupation(T/N ratio) andαvβ3 expression level were analyzed.The T/N ratios in brain glioma were proportionally correlated to av(33 positive cell percentage(R2=0.9253,p<0.05).This study primarily evaluated the clinical application of 99mTc-3PRGD2 SPECT scintigraphy on brain glioma.The more pathological types and detecting strategies covering a large amount of samples would aid to clarify the potentials. 相似文献
72.
氰化物浓度是氰化浸金工艺的重要参数,通过氰化物浓度在线检测控制可以有效减少氰化物消耗。介绍了BOTA型氰化物浓度在线分析仪的技术升级,由光度滴定替代电位滴定,提高了仪器测量性能及可靠性。升级后的BOTA-Ⅱ型氰化物浓度在线分析仪在排山楼金矿进行了工业应用,在氰化钠和某低氰药剂的浸出流程中均能实现氰化物浓度的在线测量,测量精度及可靠性满足要求,为企业带来了显著的经济效益。 相似文献
73.
Hung‐Chieh Lo Po‐Yi Chou Chun‐Chieh Huang Po‐Jui Chen Shih‐Meng Hsu 《Water and Environment Journal》2014,28(3):442-448
Drawing from the lessons learnt from the Fukushima nuclear disaster in Japan, the assessment of subsurface environmental hazard around nuclear power plants has emerged as a critical task. Consequently, aiming to better understand the possible environmental impact of radiation leaks into the groundwater, a prescreening programme was initiated in 2011 by the Taiwanese government. As part of this programme, this study conducted various borehole prospecting techniques to identify in situ hydrogeological characteristics at Chin‐Shan Nuclear Power Plant. Borehole electrical log, sonic log and temperature/conductivity log were conducted to explain the regional lithologic conditions and permeability of the formation. In conjunction with this, the interwell tracer and pumping test was carried out to simultaneously determine the hydraulic parameters. In our opinion, the implementation of such in situ end‐to‐end investigations is essential in interpreting in situ fluid and solute transport dynamics prior to programming any numerical scheme for early warning, vulnerability assessment and regular monitoring of a nuclear power plant site. 相似文献
74.
为有效封堵优势渗流通道,解决注入溶液窜流突进及沿优势渗流通道无效循环对改善油田开发效果以及达到控水稳油的目的具有重要意义。应用数值模拟示踪剂方法研究优势渗流通道的动态反映特征,筛选出影响和标志优势渗流通道存在的主要参数指标并分析其相关特性,制定基于油藏模拟的优势渗流通道判别标准和成果表征,实现定量识别优势渗流通道的方法,对油田开发控水提效具有重要意义。 相似文献
75.
Jennifer Therkorn David Drewry III Thomas Pilholski Kathryn Shaw‐Saliba Gregory Bova Lisa L. Maragakis Brian Garibaldi Lauren Sauer 《Indoor air》2019,29(1):143-155
Biocontainment units (BCUs) are facilities used to care for patients with highly infectious diseases. However, there is limited guidance on BCU protocols and design. This study presents the first investigation of how HVAC (heating, ventilation, air‐conditioning) operating conditions influence the dissemination of fluorescent tracer particles released in a BCU. Test conditions included normal HVAC operation and exhaust failure resulting in loss of negative pressure. A suspension of optical brightener powder and water was nebulized to produce fluorescent particles simulating droplet nuclei (0.5‐5 μm). Airborne particle number concentrations were monitored by Instantaneous Biological Analyzers and Collectors (FLIR Systems). During normal HVAC operation, fluorescent tracer particles were contained in the isolation room (average concentration = 1 × 104 ± 3 × 103/Lair). Under exhaust failure, the automated HVAC system maximizes airflow into areas adjacent to isolation rooms to attempt to maintain negative pressure differential. However, 6% of the fluorescent particles were transported through cracks around doors/door handles out of the isolation room via airflow alone and not by movement of personnel or doors. Overall, this study provides a systematic method for evaluating capabilities to contain aerosolized particles during various HVAC scenarios. Recommendations are provided to improve situation‐specific BCU safety. 相似文献
76.
《International Journal of Hydrogen Energy》2019,44(43):23856-23867
In this paper, the synergistic effects of advanced oxidization reactions in a combination of TiO2 photocatalysis are comparatively investigated for hydrogen production and wastewater treatment applications. An experimental study is conducted with a photoelectrochemical reactor under a UV-light source. TiO2 is selected as the photocatalyst due to the high corrosion resistant nature and ability to form hydroxyl radicals with the interaction with photons. The synergetic effects of advanced oxidization processes (AOPs) such as Fenton, Fenton-like, photocatalysis (TiO2/UV) and UV photolysis (H2O2/UV) are investigated individually and in a combination of each other. The Fenton type reagent in the reactor is formed by anodic sacrificial of stainless-steel electrode with the presence of H2O2. The influences of various parameters, including pH level, type of the electrode and electrolyte and the UV light, on the performance of the combined system are also investigated experimentally. The highest chemical oxygen demand (COD) removal efficiency is observed as 97.9% for the experimental condition which combines UV/TiO2, UV/H2O2 and photo-electro Fenton type processes. The maximum hydrogen production rate from the photoelectrolysis of wastewater is obtained as 7.0 mg/Wh for the experimental condition which has the highest rate of photo-electro Fenton type processes. The average enhancement with the presence of UV light on hydrogen production rates and COD removal efficiencies are further calculated to be 3% and 20%, respectively. 相似文献
77.
78.
《International Journal of Hydrogen Energy》2021,46(73):36023-36036
Transition metal catalysts were supposed to be the most likely substitute for commercial noble metal catalysts, and the development of highly active and long-term catalyst for water splitting are the future trend. Herein, Ni rectangular nitrogen doped carbon nanorods@Fe–Co nanocubes (Ni-CNRs@Fe–Co cubes) were fabricated via a facile template-free method. This simple strategy not only realizes the structure tailoring, but also achieves high-quality nitrogen-doping. Specifically, nickel dimethylglyoxime [Ni(dmg)2] with rectangular rodlike structure was firstly synthesized by solution method, then metal-organic frameworks Fe–Co nanocube with different contents were loaded on rectangular carbon nanorods with polydopamine as the locating and the connecting agent, and finally Ni-CNRs@xFe-Co cubes were obtained by a one-step calcination. A series of electrochemical tests were researched on materials with different metal contents in the 1 M KOH solution. The Ni-CNRs@Fe–Co cubes show excellent electrocatalytic activity in the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). For HER and OER, the Tafel slopes were 83.3 mV dec−1 and 71 mV dec−1, the onset potential were −167 mV and 1.62 V, and reached the current densities of 10 mA cm−2, the overpotential just needed 196 mV and 433 mV, respectively. This novel synthetic strategy will provide a template-free way for cheap electrocatalysts of non-precious metal for OER and HER. 相似文献
79.
We consider inverse problems in atmospheric modelling represented by a linear system which is based on a source-receptor sensitivity matrix and measurements. Instead of using the ordinary least squares, we add a weighting matrix based on the topology of measurement points and show the connection with Bayesian modelling. Since the source-receptor sensitivity matrix is usually ill-conditioned, the problem is often regularized, either by perturbing the objective function or by modifying the sensitivity matrix. However, both these approaches may be heavily dependent on specified parameters. To ease this burden, we propose to use techniques looking for a sparse solution with a small number of positive elements. Finally, we compare all these methods on the European Tracer Experiment (ETEX) data where there is no apriori information apart from the release position and some measurements. 相似文献
80.