电子应用产品的防电击试验浅析

本文依据国家有关标准对电子应用产品的防电击试验进行了简介和分析，指出了试验中应注意的问题。     

渤中凹陷深层砂砾岩气藏油气充注与储层致密化

渤海湾盆地渤中凹陷砂砾岩储层致密化成因及其与晚期油气侵位的关系一直没有得到合理地解释。为此,以渤中凹陷西南部地区古近系砂砾岩气藏为研究对象,利用物性、热史、包裹体等分析资料,确定油气首次成藏时间、划分油气充注期次、恢复成藏期储层物性,进而模拟压实作用对储层的影响,并结合包裹体、铸体、扫描电镜、X射线衍射等实验手段明确油气侵位关系,分析石英加大、黏土矿物转化、碳酸盐胶结等关键致密化作用发生的序列,探究储层致密化作用机理及其与油气充注的关系。研究结果表明:①该区深层砂砾岩油气充注至少可分为3期,早期包裹体为重质油,晚期包裹体气油比高;②首次油气充注期为距今5Ma,储层埋深介于2500～2800m,以中孔、中渗储层为主,储集物性较好,成藏后盆地快速沉降、充填,上覆地层增加厚度超过1 000 m;③首次油气充注后砂砾岩进入成岩快速演化期,埋深介于2 500～3 200 m,是砂砾岩快速压实阶段,石英加大在油气充注后经历了两期强烈发育,减孔作用明显,压实减孔作用是储层致密化的重要机制;④埋深介于2 500～3 500 m为该区黏土矿物快速转化区间,花状及丝发状伊利石极其发育,对渗透率的大小产生了决定性的影响;⑤铁方解石及铁白云石沉淀于石英加大之后,使储层进一步致密化,以残余孔隙为主。结论认为,该区古近系砂砾岩气藏具有先成藏后致密的特点,尽管油气充注对储层成岩具有抑制作用,但后者仍然会导致储层的致密化。     

Biodesulfurization of model oil using growing cells of Gordonia sp. SC-10

The biodesulfurization capacity of Gordonia sp. SC-10 in a biphasic reaction system was investigated in this study. Model oil containing dibenzothiophene was used as the sole sulfur source of bacterium. The results showed that 81.43% of the sulfur in model oil with initial sulfur content of 174?mg/l could be removed within 5?days. Gordonia sp. SC-10 had high desulfurization rate for model oils with low sulfur contents, which would reduce sulfur concentration to below 5?mg/l. Biodesulfurization process might be a potential method to obtain fuels with ultra-low sulfur contents.     

胍胶自增稠支撑剂性能及其储层伤害性评价

为大幅减少现有压裂液工艺配制和运输费用,实现在线配制携砂液,本文采用将胍胶细粉黏附在支撑剂颗粒外表面的方法制作了新型自增稠支撑剂,并以高温高矿化度油藏环境为实验条件,开展了该自增稠支撑剂性能评价及储层伤害性实验。研究表明,在温度高于80℃的情况下,与SZ36-1油田注入水、长庆油田注入水、大庆油田污水和大庆油田清水相比,由矿化度最高的大港油田注入水配制的胍胶增稠剂溶液增黏性最好,视黏度最高,储能模量最大,携砂能力最强。当砂比大于30%后,用大港油田注入水配制自增稠支撑剂悬浮时间小于20 s,沉降时间大于4 h。当自增稠支撑剂破胶剂加量为0.03%数5.0%时,破胶时间为14数2.5h。恒速实验中,随着岩心渗透率增大,滤失量逐渐升高,伤害率逐渐降低。恒压实验中,随着滤失压差的增大,滤失量逐渐增加,伤害率逐渐增加。该胍胶自增稠支撑剂可满足高温油藏压裂施工需求,具有广阔的应用前景。图5表6参20     

多特征融合的文档图像版面分析

目的 在文档图像版面分析上,主流的深度学习方法克服了传统方法的缺点,能够同时实现文档版面的区域定位与分类,但大多需要复杂的预处理过程,模型结构复杂。此外,文档图像数据不足的问题导致文档图像版面分析无法在通用的深度学习模型上取得较好的性能。针对上述问题,提出一种多特征融合卷积神经网络的深度学习方法。方法 首先,采用不同大小的卷积核并行对输入图像进行特征提取,接着将卷积后的特征图进行融合,组成特征融合模块;然后选取DeeplabV3中的串并行空间金字塔策略,并添加图像级特征对提取的特征图进一步优化;最后通过双线性插值法对图像进行恢复,完成文档版面目标,即插图、表格、公式的定位与识别任务。结果 本文采用mIOU（mean intersection over union）以及PA（pixel accuracy）两个指标作为评价标准,在ICDAR 2017 POD文档版面目标检测数据集上的实验表明,提出算法在mIOU与PA上分别达到87.26%和98.10%。对比FCN（fully convolutional networks）,提出算法在mIOU与PA上分别提升约14.66%和2.22%,并且提出的特征融合模块对模型在mIOU与PA上分别有1.45%与0.22%的提升。结论 本文算法在一个网络框架下同时实现了文档版面多种目标的定位与识别,在训练上并不需要对图像做复杂的预处理,模型结构简单。实验数据表明本文算法在训练数据较少的情况下能够取得较好的识别效果,优于FCN和DeeplabV3方法。     

平行和垂直交叉排列组合棒介质高梯度磁选对比研究

为研究棒介质排列组合对高梯度磁选效果的影响,应用"单元介质分析法",选择铁品位38.10%的细粒赤铁矿,进行棒介质丝平行与垂直交叉排列组合对比研究。结果表明,与单一丝径棒介质比较,不同丝径组合式棒介质可以兼顾对不同粒级磁性矿粒的选择性捕获,有利于提高分选指标,且组合程度越高,提升分选指标越明显;介质丝平行与垂直交叉排列组合各有特点,后者捕获概率大些,但夹杂现象多些,因此精矿产率和铁回收率更高,但精矿品位更低。     

半无限大生物组织中光子分布规律的研究

光子在生物组织中的传播和分布问题, 是影响光动力疗法治疗结果的重要因素之一。本文给出了蒙特卡罗方法模拟半无限大均匀生物组织中光子分布的计算方法和模拟结果, 分析了半无限大生物组织中光子分布规律。结果表明, 生物组织的光学性质强烈影响光在组织中的分布情况。具有低散射系数, 低吸收系数和高各项异性因子的生物组织, 有利于光子深入均匀地分布其中。力图为光动力疗法的临床应用提供了有效的诊断和治疗依据。     

物理升华法生长ZnO晶体的研究

Zinc oxide（ZnO） has a wide band gap, high stability and a high thermal operating range that makes it a suitable material as a semiconductor for fabricating light emitting diodes（LEDs） and laser diodes, photodiodes, power diodes and other semiconductor devices. Recently, a new crystal growth for producing ZnO crystal boules was developed, which was physical vapor transport（PVT）, at temperatures exceeding 1500 ？C under a certain system pressure. ZnO crystal wafers in sizes up to 50 mm in diameter were produced. The conditions of ZnO crystal growth, growth rate and the quality of ZnO crystal were analyzed. Results from crystal growth and material characterization are presented and discussed. Our research results suggest that the novel crystal growth technique is a viable production technique for producing ZnO crystals and substrates for semiconductor device applications.     

Guanidine and Galactose Decorated Nanophotosensitizer with Oxygen Self-Sufficient Capability for the Localized Ablation of Oral Biofilm

Dental caries is a common disease caused by plaque biofilms, which are important pathogenic factors in many diseases. When hosts are overexposed to dietary sugars, pathogens such as Streptococcus mutans (S. mutans) and other cariogenic bacteria, metabolically assemble an extracellular matrix rich in exopolysaccharides to form a disease-causing biofilm, in which the microenvironment is characterized by regional hypoxia, low pH, and nutritional deprivation. Current antimicrobials with inadequate penetration and a lack of pathogens targeting the biofilm do not degrade the protective matrix within the biofilm. In this study, a guanidine and galactose decorated nanophotosensitizer with oxygen self-sufficient capability, p(GF/GEF)-I, is developed to enhance the permeability of biofilms by positively charging the particle surface and easily binding to the bacteria within the membrane through electrostatic interactions. 90% of the biofilm on enamel surface is eliminated after treatment with p(GF/GEF)-I under laser irradiation. Notably, the nanophotosensitizer inhibits the recolonization of dental biofilms by S. mutans, preventing secondary infections. Furthermore, dental caries in a rodent model are reduced with exposure to nanophotosensitizer. p(GF/GEF)-I is a significantly higher efficacy without damaging the surrounding soft tissue. With further development and optimization, p(GF/GEF)-I shows significant potential as a phototherapeutic agent for the treatment of biofilm-induced diseases.     

Partial segmented compressed sampling for analog-to-information conversion

Recently, a segmented analog-to-information conversion (S-AIC) structure that can obtain more samples than the number of branches of mixers and integrators (BMIs) is proposed by Taheri and Vorobyov. To reduce the complexity of S-AIC, in this paper we propose a partial segmented AIC (PS-AIC) structure, where BMIs are divided into groups and each group only works within a partial period that is non-overlapping in time. The proposed PS-AIC offers an attractive tradeoff between the complexity and error performance. We also prove that the equivalent measurement matrix of PS-AIC satisfies the restricted isometry property. Simulations verify the effectiveness of PS-AIC.