工程机械齿轮传动系统噪声分析与控制

论述齿轮传动系统噪声产生的原因及频谱分析方法。介绍多种降低噪声的措施 ,提出一些低噪声工程机械设计原则     

The Role of Transmembrane Proteins in Plant Growth,Development, and Stress Responses

Transmembrane proteins participate in various physiological activities in plants, including signal transduction, substance transport, and energy conversion. Although more than 20% of gene products are predicted to be transmembrane proteins in the genome era, due to the complexity of transmembrane domains they are difficult to reliably identify in the predicted protein, and they may have different overall three-dimensional structures. Therefore, it is challenging to study their biological function. In this review, we describe the typical structures of transmembrane proteins and their roles in plant growth, development, and stress responses. We propose a model illustrating the roles of transmembrane proteins during plant growth and response to various stresses, which will provide important references for crop breeding.     

加快煤矿智能化建设推进煤炭行业高质量发展

引入图像语义分割技术,对矿井次光照环境中的目标物进行分割,将图像分成原始清晰图像和次光照图像两类,采用基于深度学习的图像增强方法对次光照条件下拍摄的图像增强细节后替换,再利用单应变换算法对数据集进行扩充,进而构建矿井巷道图像语义分割标准数据集。提出一种基于自注意力机制的轻量级编码—解码结构网络：以DeepLab V3+编码—解码网络为基础网络,在编码结构中,提取矿井图像深、浅层语义特征信息,将深层语义特征信息经由轻量级自注意力机制模块进行特征激活,而浅层语义特征信息直接送入解码器中,在解码结构中拼接深、浅层语义特征信息,恢复原始图像尺寸,输出分割结果。与传统算法就图像预测进行对比实验,结果表明：在网络复杂度方面,对于3通道512×512像素大小的图像,算法的网络理论计算量FLOPs仅48.80 G,参数量仅11.90 M;在网络分割精度方面,平均交并比76.50%,平均像素精度87.75%,领先其他主流网络;在速度方面,推理一张图像的速度能达到0.032 s,可满足轻量级网络的要求。

     

高放废液合成岩石固化研究

建立了高效废液合成岩石固装置，确定了固化工艺和性能测试方法，制备的合成岩石固化体样吕测试样结果表明，采用的实验装置，工艺流程和测试方法可行，将Ｎａ０．５ＲＥＥ０．５ＴｉＯ３型钙钛矿和Ｎａ２Ａｌ２ＴｉＯ８Ｏ１６型黑钛铁钠矿作为包容钠的主要矿相，分别研制了国内生产高放废液的合成岩石基料配方，氧化钠的包容量可达５．７％。     

STUDY OF THE COARSE GRAINS OF QUENCHED LD2 ALLOY FORGING

LD2合金锻件的中心部位,淬火后如出现粗大晶粒,会造成废品。本文通过对锻件生产的模拟试验——镦粗件,用X射线衍射和金相方法,研究了一些工艺因素(如变形量,变形及淬火温度,保温时间等)对形成粗晶的影响,阐明了粗晶出现的规律,生成机理和消除粗晶的途径。     

硼锂玻璃与珍珠岩玻璃的研制及工艺试验

研制了用于固化高放废液的硼锂玻璃504~#和珍珠岩玻璃7920~#二种配方。并在工程冷试验装置上进行了玻璃固化工艺试验。本文介绍这二种玻璃的组成、工艺流程及试验结果。     

高效气-液聚结器在LPG回收装置中的应用

文昌13-1/2油田LPG回收装置进口涤气罐使用传统的除液工艺不能有效地除去伴生气中的液体,严重影响LPG系统的正常生产.应用新型高效气-液高效聚结器对进LPG回收装置的伴生气进行气液分离后,操作状况明显改善,节约后续设备维修保养费用,提高LPG的生产时效,年经济效益200万元以上,还可以起到节能减排的目的.     

铜绿山铜铁矿大直径深孔采矿技术试验研究

铜绿山铜铁矿采用大直径深孔采矿方法(VCR法)开采。多年来采场跨塌频繁,严重地影响了生产,并带来很大的采矿贫化损失。调查表明,岩性变差与凿岩爆破工艺不合理是采场跨塌的主要诱因。为此,将VCR法爆破改为后退式分段侧向多排微差控制爆破,并在不稳固地段和采场边孔采用不耦合装药方式实行减弱装药。对孔内爆轰波的试验研究表明,不耦合条状药包爆破的爆轰波传播距离可达6m以上,无需增加起爆弹可直接起爆下一分段的药包。为此将弱间隔的2段药包,合并为1段起爆。该法简化了装药结构,方便了减弱装药措施的实施。另外,为减少爆尘、减轻炮泥搬运负担,试验采用了水封爆破。该工艺在7313采场经过1a多的试验,获得了预期满意的效果,随后在全矿类似矿体推广应用,解决了矿山多年来因采场跨塌带来的负面影响。     

Sorption and displacement of pyrene in soils and sediments

Sorption isotherms of pyrene on soils and sediments were examined to understand its sorption behavior. All systems examined exhibited nonlinear sorption. Sorption nonlinearity was found to be a function of the polarity index of soil/sediment organic matter (SOM), suggesting that the degree of condensation of SOM, characterized by its polarity index, was correlated with the sorption behavior of pyrene. The polarity index of SOM could be a new factor for explaining the sorption nonlinearity. The sorption affinity of two soils and two sediments for pyrene increased with decreasing SOM polarity. A higher sorption affinity in the two soils was associated with a higher degree of condensation of SOM compared to that of the two sediments. A displacement test was performed after pyrene sorption using phenanthrene as a displacer. Pyrene was displaced in all systems examined, and nonlinearity became less pronounced after displacement. Such an increase in isotherm linearity implied that sorption site energies became more homogeneous after displacement. Furthermore, the site energy distribution IE*) derived from the Freundlich model parameters showed that energy reduction of high-energy sites was more significant than that of low-energy sites after displacement. In addition, a decrease in sorption capacity after displacement could be ascribed to the partial depletion of sorption sites by the displacer. The displacement data indicated that the cocontaminant can have potential effects on the fate and bioavailability of anthropogenic organic pollutants sorbed in soils and sediments, thus affecting their exposure risks.     

Xylem- and phloem-based transport of CuO nanoparticles in maize (Zea mays L.)

This work reports on the toxicity of CuO nanoparticles (NPs) to maize (Zea mays L.) and their transport and redistribution in the plant. CuO NPs (100 mg L(-1)) had no effect on germination, but inhibited the growth of maize seedlings; in comparison the dissolved Cu(2+) ions and CuO bulk particles had no obvious effect on maize growth. CuO NPs were present in xylem sap as examined by transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS), showing that CuO NPs were transported from roots to shoots via xylem. Split-root experiments and high-resolution TEM observation further showed that CuO NPs could translocate from shoots back to roots via phloem. During this translocation, CuO NPs could be reduced from Cu (II) to Cu (I). To our knowledge, this is the first report of root-shoot-root redistribution of CuO NPs within maize. The current study provides direct evidence for the bioaccumulation and biotransformation of CuO NPs (20-40 nm) in maize, which has significant implications on the potential risk of NPs and food safety.