Influence of Non-Natural Ageing Temperature on the Microstructural Characteristics and Mechanical Properties of Cast Aluminum 6063 Alloy

This research considered the effect of non-natural aging on the microstructural characteristics and mechanical properties of as-cast aluminum 6063 alloys. The samples were developed through a sand casting process and machined into tensile and impact test samples before carrying out solution heat treatment at 550?C (0.83 Tm) on two parts of the samples while retaining one part as the control. The two parts were further divided into sets denoted A and B and were aged at 180?C (0.27 Tm) and 160?C (0.24 Tm), respectively, for 12 hours. The results showed that sample A has the optimal yield strength and ultimate tensile strength of 192 and 206 MPa, respectively. Likewise, the sample gave the highest impact strength value of about 9.63 J/mm2. The observed results were supported by the optical micrograph, which revealed that the sample has evenly dispersed precipitates in its microstructure. This is deemed responsible for the observed increase in strength of the sample.

All-optical Quantitative Framework for Bioluminescence Tomography with Non-contact Measurement

In this contribution, we present an all-optical quantitative framework for bioluminescence tomography with non-contact measurement. The framework is comprised of four indispensable steps： extraction of the geometrical structures of the subject, light flux reconstruction on arbitrary surface, calibration and quantification of the surface light flux and internal bioluminescence reconstruction. In particular, the geometrical structures are retrieved using a completely optical method and captured under identical viewing conditions with the bioluminescent images. As a result, the proposed framework avoids the utilization of computed tomography or magnetic resonance imaging to provide the geometrical structures. On the basis of experimental measurements, we evaluate the performance of the proposed all-optical quantitative framework using a mouse shaped phantom. Preliminary result reveals the potential and feasibility of the proposed framework for bioluminescence tomography.

Non-metallic Inclusions in Continuously Cast Aluminum Killed Steels

In aluminum killed steels, the size, shape, quantity and formation of non-metallic inclusions in ladle steel (before and after RH vacuum treatment) and in tundish as well as in slabs were studied by EPMA (Electron Probe Microanalysis) and by analyzing the total oxygen. The results showed that in the slabs the total oxygen was quite low and the inclusions discovered were mainly small-sized angular alumina inclusions. This indicates that most inclusions have been removed by floating out during the continuous casting process. In addition, the countermeasures were discussed to decrease the alumina inclusions in the slabs further.

Preparation &Microscopic Characterization of Non-Chrome Chemical Conversion Film in Aluminum Surface

A chromium-free environmental protection aluminum surface treatment technology was developed by theoretical analysis and a large number of experiments. Add zirconium ions and cerium ions to the treatment solution, besides adding fluoride, aluminum and hydrogen peroxide, etc. According to the orthogonal test obtained a non-chromate film-formation process of environmental friendly aluminum. The characterization methods including SEM, XPS and XRD were applied to study and analyze the morphology, composition, phase, and corrosion resistance of phosphate film, then discussed the film-forming reaction mechanism. Results showed that chemical conversion film formed on the aluminum surface was uniform, compact and stronger anti-corrosion could replace the traditional, more toxic chromate conversion film.

Structural evolution of non dendritic AlSi7Mg alloy during reheating

The structural evolution of non dendritic AlSi7Mg alloy during reheating in resistance furnace was studied. The alloy ingots were produced by electromagnetic stirring during solidification. It was found that, the Si phase in eutectic dissolves in a way of diffusion toward α phase, its appearance changes from flake to dot like, and tends to be fine and spheroidal with increasing reheating temperature. The thinner the flake, the lower the temperature for the occurrence of this process, and the higher the transforming speed. The eutectic melts partially when Si phase dissolves to some extent, and the morphology and size of primary α phase begin to change. The dendrite and rosette α phases tends to sphericize. The size of the former becomes larger, while the size of the latter reduces to be 1/2～1/4 of the original size. The spheroidal primary α phase has a tendency of grain growth.

Formation and Evolution of Non-dendritic Microstructures of Semisolid Alloys Prepared by Shearing/Cooling Roll Process

The shearing/cooling roll （SCR） process was adopted to prepare semi-solid A2017 alloy. The formation and evolution of non-dendritic microstructures in semi-solid A2017 alloy were studied. It is shown that the microstructures of semi-solid billets transform from coarse dendrites into fine equiaxed grains as the pouring temperature of molten alloy decreases o.r roll-shoe cavity height is reduced. From the inlet to the exit of roll-shoe cavity, microstructure of semi-solid slurry near the shoe surface is in the order of coarse dendrites, degenerated dendrites or equiaxed grains, but fine equiaxed grains are near the roll surface. Microstructural evolution of semi-solid slurry prepared by SCR process is that the molten alloy nucleates and grows into dendrite firstly on the roll and shoe＇s surface. Under the shearing and stirring given by the rotating roll, the dendrites crush off and disperse into the melt. Under the shearing and stirring on semi-solid slurry with high volume fraction of solid, the dendrite arms fracture and form equiaxed grain microstructures.

The fabrication of homogeneous perovskite films on non-wetting interfaces enabled by physical modification

Conjugated polymers are commonly used as effective hole transport materials(HTMs) for preparation of high-performance perovskite solar cells. However, the hydrophobic nature of these materials renders it difficult to deposit photovoltaic perovskite layers on top via solution processing. In this article, we report a generic surface modification strategy that enables the deposition of uniform and dense perovskite films on top of non-wetting interfaces. In contrast to the previous proposed chemical modifications which might alter the optoelectronic properties of the interfacial layers, we realized a nondestructive surface modification enabled by introducing a layer of insulating mesoporous aluminum oxide(Al2O3). The surface energies of the typical non-wetting hole-transport layers(PTAA, P3 HT, and Poly-TPD) were significantly reduced by the Al2O3 modification. Benefiting from the intact optoelectronic properties of the HTMs, perovskite solar cells deposited on these interface materials show full open-circuit voltages( V OC) with high fill factors(FF) up to 80%. Our method provides an effective avenue for exploiting the full potential of the existing as well as newly developed non-wetting interface materials for the fabrication of high-performance inverted perovskite solar cells.

Unified Framework Towards Flexible Multiple Access Schemes for 5G

Non-orthogonal multiple access （NOMA） schemes have achieved great attention recently and been considered as a crucial compo-nent for 5G wireless networks since they can efficiently enhance the spectrum efficiency, support massive connections and poten-tially reduce access latency via grant free access. In this paper, we introduce the candidate NOMA solutions in 5G networks, com-paring the principles, key features, application scenarios, transmitters and receivers, etc. In addition, a unified framework of these multiple access schemes are proposed to improve resource utilization, reduce the cost and support the flexible adaptation of multi-ple access schemes. Further, flexible multiple access schemes in 5G systems are discussed. They can support diverse deployment scenarios and traffic requirements in 5G. Challenges and future research directions are also highlighted to shed some lights for the standardization in 5G.

Improved strength and ductility of high alloy containing Al–12Zn–3Mg–2.5Cu alloy by combining non-isothermal step rolling and cold rolling

Al-12Zn-3Mg-2.5Cu alloy was prepared using a liquid metallurgy route under the optimized conditions. A sample cut from the ingot was rolled non-isothermally from 400℃ to 100℃ in 100℃ steps, with 15% reduction in thickness; it was then cold rolled isothermally at room temperature for 85% reduction. The cold-rolled alloys were characterized by electron microscopy, hardness test, and tensile test to elucidate their structural evolution and evaluate their mechanical behavior. In the results, the cast alloy consists of a-aluminum and various intermetallic compounds. These compounds are segregated along the grain boundaries, which makes the alloy difficult to roll at room tem- perature. The combined effect of non-isothermal step rolling and cold rolling results in the nano/microsized compounds distributed uniformly in the matrix. The hardness is substantially increased after rolling. This increase in hardness is attributed to the ultra-fine grain size, fine-scale intermetallic compounds, and structural defects （e.g., dislocations, stacking faults, and sub-grains）. The ultimate tensile strength of the rolled alloy is approximately 628 MPa with 7% ductility.

Effect of barium on the refinement of primary aluminum and eutectics in a hypoeutectic Al-Si alloy

The effect of barium on the refinement of primary aluminum and on themodification of eutectics in a hypoeutectic aluminum-silicon alloy was investigated. The resultsindicate that barium not only modifies the eutectic silicon but also refines the primary aluminumand there is a relationship between the retained barium and the second spacing of primary aluminum.Experiments of barium-treated commercial Al-Si hypoeutectic alloy show that barium is a bettermodifier than sodium when there is a longer holding time.

Research Progress of Magnesium Stabilized Aluminum Titanate and New Application of It in Pigment

Aluminum titanate has been widely used in low expansion applications and its thermal stability has been a hot topic. The stability of aluminium titanate research for improving product quality, and expanding its application field is of great significance. Aluminum titanate as glass melt erosion resistance and high temperature resistant, can be applied to high temperature pigment base. The medium temperature stability of aluminum titanate can be improved by ion doping, and magnesium stability of aluminum titanate has been widely studied. Therefore aluminium titanate is expected to become an ideal high temperature ceramic base material. In this paper, the preparation technology of magnesium-stabilized aluminum titanate powder was reviewed, and the preparation of magnesium-stabilized aluminum titanate powder by non-hydrolyzed sol-gel was mainly introduced.

炸药爆轰环境中铝粉非等温燃烧模型

为研究铝粉在爆轰环境中的燃烧特性,基于爆轰环境中铝粉燃烧模型,综合考虑了爆轰产物气体组分和爆轰环境体系温度对铝粉燃烧释能过程的影响,建立了爆轰环境中铝粉非等温燃烧模型,提出了包括铝粉燃烧过程、爆轰产物气体组分和爆轰环境体系温度在内的爆轰环境铝粉非等温燃烧控制方程,并通过激光诱导击穿光谱实验进行了验证。结果表明,铝粉非等温燃烧模型控制方程的计算值与激光诱导击穿光谱实验值的偏差在12%以内,验证了理论模型计算的准确性,获得了铝粉粒度和铝氧比对炸药中铝粉燃烧特性的影响规律。

SOSNet:一种非对称编码器-解码器结构的非小细胞肺癌CT图像分割模型

非小细胞肺癌严重损害人类健康,早期非小细胞肺癌CT(Computed Tomography)图像中的肿瘤结节体积小,不易发现,极易造成漏诊和误诊.为了精确分割非小细胞肺癌CT图像中的小体积肿瘤结节,本文提出SOSNet(Small Object Segmentation Networks)自动分割模型,利用ResNet(Residual Network)基础层和空洞卷积构造非对称编码器-解码器结构作为分割主网络,利用轴向取反注意力模块ARA(Axial Reverse Attention)逐步擦除背景中对分割有影响的结构,再使用结构细化模块SR(Structure Refinement)对主网络输出的粗略特征图进行结构细化,从而实现非小细胞肺癌肿瘤结节分割.在非小细胞肺癌公开数据集的实验测试表明,本文提出的小目标自动分割模型SOSNet可以有效分割出非小细胞肺癌CT图像中的小体积肿瘤结节,其mDice(mean-Dice)、mIoU(mean Intersection over Union)、Sensitivity、F1、Specificity、平均绝对误差MAE(Mean Absolute Error)均优于当前最先进的小目标分割模型CaraNet(Context Axial Reverse Attention Network).

地震事件分类识别软件

非天然地震事件分类是地震监测业务部门的日常工作之一。本研究主要针对地震、爆炸和矿震的分类问题,在地震波数据处理、特征提取和人工智能综合分类的研究基础上,基于Qt开发框架,结合Python、 Matlab等多种编程语言,开发了一个具有良好的可移植性和可扩展性、具有自主知识产权的地震分类识别软件。该软件可以部署在不同操作系统上,由七个模块组成:地震数据导入模块、数据处理模块、特征提取模块、综合分类模块、特征分析模块、当量估算模块和结果分析模块。软件集成了多种时频特征提取技术和人工智能分类方法,形成了较为完整的地震类型判定流程。软件内置的地震事件分类模型准确率高于90%,适用范围较广,已推广应用于多个地震监测部门,并取得了较好的应用成果,提高了对非天然地震的快速分析能力。

Functionality of Covalent Organic Framework (COF) in Gas Storage Application: First Principal Study

Industrial growth in recent years led to air pollution and an increase in concentration of hazardous gases such as O3 and NO. Developing new materials is important to detect and reduce air pollutants. While catalytic decomposition and zeolites are traditional ways used to reduce the amount of these gases. We need to develop and explore new promising materials. Covalent organic framework (COF) has become an attractive platform for researcher due to its extended robust covalent bonds, porosity, and crystallinity. In this study, first principal calculations were performed for gases adsorption using COFs containing nitrogen and π-bonds. Different building blocks (BBs) and linkers (LINKs/LINK1 & LINK2) were investigated by means of density functional theory (DFT) calculations with B3LYP and 3-21G basis sets to calculate the binding energies of gases @COF systems. Electrostatic potential maps (ESPM), Mulliken charges and non-covalent interaction (NCI) are used to understand the type of interactions between gas and COFs fragments. O3 was found to bind strongly with COF system in comparison with NO which could make COF a useful selective material for mixed gases environment for sensing and removal application.

整合服务型框架下多维度照护策略对NSCLC患者应对方式、癌因性疲乏的影响

目的探究整合服务型框架下多维度照护策略对非小细胞肺癌(NSCLC)患者患者应对方式、癌因性疲乏(CRF)的影响。方法按照随机数字表法将2021年4月至2022年6月河南科技大学第一附属医院肿瘤内科收治的103例NSCLC患者分为观察组(52例)和对照组(51例)。对照组接受常规护理,观察组在对照组基础上接受整合服务型框架下多维度照护策略。对比两组患者应对方式、CRF程度、自我效能感评分、生活质量评分及护理满意度。结果护理后观察组面对评分、生活质量及自我效能感得分均高于对照组、屈服和回避评分及CRF评分均低于对照组(P<0.05);观察组护理满意度高于对照组(P<0.05)。结论整合服务型框架下多维度照护策略可有效改善患者应对方式并减轻患者癌因性疲乏,从而促进患者自我效能感和生活质量的提升并提高患者满意度。

冷却速率对Al-50%Si合金微观组织的影响

采用熔体水淬法(水冷法)、气雾化法和单辊熔融纺丝技术(甩带法)制备不同冷却速率的快速凝固过共晶Al-50%Si合金,并通过扫描电子显微镜(scanning electron microscope,SEM)和X射线衍射仪(X-ray diffractometer,XRD)分析了快速凝固与常规凝固的差异,以及快速凝固Al-50%Si合金微观组织的演变。结果表明:在水冷的Al-50%Si合金组织中观察到了树枝状的Al相,较大的过冷度导致这种亚共晶组织的形成,此组织属于非稳定状态,且共晶Si完全细化至纤维状;随着冷却速率的增加,在甩带试样中Al相的树枝状组织消失;通过甩带以及气雾化制备的Al-50%Si合金中,初晶Si颗粒被明显细化,由常规凝固的200μm细化至20μm左右,使Si在Al基体中的固溶度增大,造成Al基体晶格发生畸变。

赤泥用于酸性含锰废水中锰的净化研究

采用还原焙烧-磁选预处理赤泥,得到非磁性物;非磁性物经煅烧、盐酸溶出后加入饱和偏铝酸钠聚合剂聚合后过滤、熟化制备聚合氯化铝(PAC)基液;使用该PAC基液,在沉降时间5 h、PAC基液与废水体积比1∶120、搅拌转速140 r/min、pH值8、反应温度30℃、聚丙烯酰胺(PAM)投加量20 mg/L条件下处理含锰酸性废水,处理后液中锰质量浓度由325.3 mg/L降至1.5 mg/L,锰去除率达99.5%,净化后液中锰质量浓度达到国家一级排放标准。

新型磷酸二氢铝镓金属无机骨架结构的合成及其催化乙醛制备丁醇醛的研究

通过水热法制备了一种新型磷酸二氢铝镓(GAHPO)金属无机骨架结构,并通过单晶XRD、粉末XRD、红外,以及TG-DSC等分析手段对其进行充分表征。单晶XRD解析表明,该晶体属于三方晶系、Rc3空间群。Al(Ga)O_(6)八面体与PO_(4)四面体结构交替连接形成一维链状金属骨架,并由氢键堆叠成三维金属无机骨架结构。TG-DSC分析显示,GAHPO热稳定性良好,初始分解温度达到240℃。相比磷酸铝,Ga^(3+)的引入使磷酸铝晶格畸变,削弱了Al—O的强度,增大了Al—O键长,使更多酸性位点暴露,从而提高GAHPO的催化活性。实验结果表明,反应温度在60℃,催化剂用量为10%时,GAHPO催化乙醛缩合制备丁醇醛具有良好的转化率(47%)和优异的选择性(>99%)。酸/碱中和催化剂、NH_(3)-TPD,以及大位阻基团取代乙醛反应位点的实验验证了GAHPO的催化乙醛缩合的反应机理。本工作为新型铝基无机骨架结构及其催化应用提供了可行途径。

三水铝石和勃姆石吸附行为的研究进展

三水铝石和勃姆石不仅是在土壤和水环境中分布广泛的铝氢氧化物矿物,也是重要的工业原料与产品。它们与环境中无机非金属离子、无机金属离子及有机物的吸附作用极大地影响着地表环境中物质的迁移富集和环境污染物的吸附去除,并且由于结构特性和表面性质,三水铝石和勃姆石在研究高效经济的吸附剂方面也具有较为重要的应用。本文在概述三水铝石和勃姆石结构和表面物理化学性质的基础上,对三水铝石和勃姆石表面多种非金属离子、金属离子和有机物的吸附行为进行综述,期望加深对铝氢氧化物矿物在地表环境物质循环中所起作用的理解,以及拓展其工业应用。