Investigation and improvement of tiny spot defects on hot-dip galvanized automotive steel sheets

The causes of tiny spot defects on the surface of hot-dip galvanized automotive steel sheets were studied using scanning electron microscopy(SEM)and energy dispersive spectrometer(EDS),and effective control measures were introduced.The results show that rubbing against the top roller after galvanizing is easy due to the local thickness of tiny spot defect location coating;therefore,the surface morphology is different from the normal part.Three kinds of defects,namely zinc slag,small slivers,and pitting,are likely to cause local thickening of the coating after galvanizing,leading to the formation of tiny spots.Therefore,resolving the three types of defects can effectively control the generation of tiny spot defects.Among them,due to the hereditary nature of the small sliver defect,focusing on its control and supervision is necessary.

Study on Licker-In and Flat Speeds of Carding Machine and Its Effects on Quality of Cotton Spinning Process

Spinning has a significant influence on all textile processes. Combinations of all the capital equipment display the process’ critical condition. By transforming unprocessed fibers into carded sliver and yarn, the carding machine serves a critical role in the textile industry. The carding machine’s licker-in and flat speeds are crucial operational factors that have a big influence on the finished goods’ quality. The purpose of this study is to examine the link between licker-in and flat speeds and how they affect the yarn and carded sliver quality. A thorough experimental examination on a carding machine was carried out to accomplish this. The carded sliver and yarn produced after experimenting with different licker-in and flat speed combinations were assessed for important quality factors including evenness, strength, and flaws. To account for changes in material qualities and machine settings, the study also took into consideration the impact of various fiber kinds and processing circumstances. The findings of the investigation showed a direct relationship between the quality of the carded sliver and yarn and the licker-in and flat speeds. Within a limited range, greater licker-in speeds were shown to increase carding efficiency and decrease fiber tangling. On the other hand, extremely high speeds led to more fiber breakage and neps. Higher flat speeds, on the other hand, helped to enhance fiber alignment, which increased the evenness and strength of the carded sliver and yarn. Additionally, it was discovered that the ideal blend of licker-in and flat rates varied based on the fiber type and processing circumstances. When being carded, various fibers displayed distinctive behaviors that necessitated adjusting the operating settings in order to provide the necessary quality results. The study also determined the crucial speed ratios between the licker-in and flat speeds that reduced fiber breakage and increased the caliber of the finished goods. The results of this study offer useful information for textile producers and process engineers to improve the quality of carded sliver and yarn while maximizing the performance of carding machines. Operators may choose machine settings and parameter adjustments wisely by knowing the impacts of licker-in and flat speeds, which will increase textile industry efficiency, productivity, and product quality.

Study on Licker-In and Flat Speeds of Carding Machine and Its Effects on Quality of Cotton Spinning Process

Spinning has a significant influence on all textile processes. Combinations of all the capital equipment display the process’ critical condition. By transforming unprocessed fibers into carded sliver and yarn, the carding machine serves a critical role in the textile industry. The carding machine’s licker-in and flat speeds are crucial operational factors that have a big influence on the finished goods’ quality. The purpose of this study is to examine the link between licker-in and flat speeds and how they affect the yarn and carded sliver quality. A thorough experimental examination on a carding machine was carried out to accomplish this. The carded sliver and yarn produced after experimenting with different licker-in and flat speed combinations were assessed for important quality factors including evenness, strength, and flaws. To account for changes in material qualities and machine settings, the study also took into consideration the impact of various fiber kinds and processing circumstances. The findings of the investigation showed a direct relationship between the quality of the carded sliver and yarn and the licker-in and flat speeds. Within a limited range, greater licker-in speeds were shown to increase carding efficiency and decrease fiber tangling. On the other hand, extremely high speeds led to more fiber breakage and neps. Higher flat speeds, on the other hand, helped to enhance fiber alignment, which increased the evenness and strength of the carded sliver and yarn. Additionally, it was discovered that the ideal blend of licker-in and flat rates varied based on the fiber type and processing circumstances. When being carded, various fibers displayed distinctive behaviors that necessitated adjusting the operating settings in order to provide the necessary quality results. The study also determined the crucial speed ratios between the licker-in and flat speeds that reduced fiber breakage and increased the caliber of the finished goods. The results of this study offer useful information for textile producers and process engineers to improve the quality of carded sliver and yarn while maximizing the performance of carding machines. Operators may choose machine settings and parameter adjustments wisely by knowing the impacts of licker-in and flat speeds, which will increase textile industry efficiency, productivity, and product quality.

离心泵网格划分中Sliver单元的消除

Sliver单元的存在严重影响着离心泵网格的质量。针对这一问题研究了离心泵网格划分中可能出现Sliver单元的位置。介绍了目前两种主要Sliver单元消除方法并总结了这两种方法的优缺点,重点分析了通过加密消除Sliver单元算法的原理,指出现有算法并不能完全消除Sliver单元。对一种现有较优的消除算法进行了改进,优化了其判断Sliver单元的准则,从而使其能在加密后完全消除Sliver单元,进而显著地提高了网格的总体质量,并将该改进算法应用于离心泵网格划分中。实例验证,改进后的算法严密有效、执行效率高,且易于实现。

Distribution characteristics of inclusions along with the surface sliver defect on the exposed panel of automobile:A quantitative electrolysis method

The specific distribution characteristics of inclusions along with the sliver defect were analyzed in detail to explain the formation mechanism of the sliver defect on the automobile exposed panel surface.A quantitative electrolysis method was used to compare and evaluate the three-dimensional morphology,size,composition,quantity,and distribution of inclusions in the defect and non-defect zone of automobile exposed panel.The Al2O3 inclusions were observed to be aggregated or chain-like shape along with the sliver defect of about 3–10μm.The aggregation sections of the Al2O3 inclusions are distributed discretely along the rolling direction,with a spacing of 3–7 mm,a length of 6–7 mm,and a width of about 3 mm.The inclusion area part is 0.04%–0.16%with an average value of 0.08%,the inclusion number density is 40 mm−2 and the inclusion average spacing is 25.13μm.The inclusion spacing is approximately 40–160μm,with an average value of 68.76μm in chain-like inclusion parts.The average area fraction and number density of inclusions in the non-defect region were reduced to about 0.002%and 1–2 mm^−2,respectively,with the inclusion spacing of 400μm and the size of Al2O3 being 1–3μm.

Redistribution of Impurity and Visible Foreign Matter in Cotton during Carding

Impurity redistribution during cotton carding was investigated. The content and size of impurity in card sliver,takerin droppings,flat strips,and cylinder screen droppings (including droppings under cylinder screen and cylinder-doffer triangle section)at four taker-in speeds were tested by using USTER AFIS. Results show that both total impurities and visible foreign matter (VFM)weights are increased. Impurities in cotton lap are carded and redistributed in card sliver, taker-in droppings, flat strips and cylinder screen droppings. Impurity percentage in taker-in droppings are the highest,followed by that in card sliver,that in flat strips and that in cylinder screen droppings. Cylinder screen has better dust-removing efficiency than flats. The average sizes of impurities in card sliver and cylinder screen droppings are decreased,whereas those of flat strips are increased and those of taker-in droppings is almost the same,in comparison with cotton lap. The impurity contents of card sliver,taker-in droppings,flat strips and cylinder screen droppings have tendencies to decrease with the increase of taker-in speed.

Crystal Structure of a Hexanuclear Silver（Ⅰ） Compound [Ag_6L^66]·4DMF and Luminescence Discussion of a Series of Silver（Ⅰ） Clusters

A new silver（Ⅰ） compound 6 （[Ag6L66]·4DMF） containing thiosemicarbazone with the group of 2-chloro-1-benzene was synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analysis and fluorescence spectrum. The title compound 6 crystallizes in monoclinic, space group C2/c with a = 26.9236（18）, b = 15.2553（8）, c = 24.6237（13） , β = 103.0680（10）°, V = 9851.7（10）3, C58H66Ag6Cl6N20O3S6, Mr = 2143.59, Dc = 1.445 g/cm3, μ（MoKα） = 1.503 mm-1, F（000） = 4232, Z = 4, the final R = 0.0565 and wR = 0.1654 for 5831 observed reflections （Ⅰ 〉 2σ（Ⅰ））. Similar to the structure of the compounds we have reported, compound 6 also exhibits a hexanuclear silver（Ⅰ） cluster. In the cluster, the S atom of ligand L6 （L6 = 2-chloro-1-benzaldehyde thiosemicarbazone） served as a triply bridged chelator to connect the six silver atoms into a Ag6L66 cluster. The luminescence property of compound 6 was investigated at room temperature and compared with other similar compounds in order to find the factors influencing their luminescent property.

Research on surface defects and continuous casting process of Fe-Ni alloy

Over the last decade,various Fe-Ni alloys have been developed at Baosteel using the EAF-AOD-LFVD-CC route. This paper first reveals the main cause of defects in Fe-Ni alloys,including surface edge cracks on hot-rolling strips and slivers on cold-rolling strips of Fe-36% Ni alloy. Then,the material properties and in-situ solidification behavior w ere experimentally investigated. The gas content and average diameter of the inclusions in Fe-36% Ni alloy that occur along the EAF-AOD-LF-VD-CC route w ere also investigated via potentiostatic electrolysis using a non-aqueous organic electrolytic. Furthermore,the heat transfer and solidification in a continuous casting mold w ere predicted based on an inverse heat transfer model using the measured mold temperature. Experimental results show that the gas content,w hich is < 0. 001 5% in a continuous casting slab,and the average diameter of the inclusions both decrease during the metallurgical EAF-AOD-LF-VD-CC process. The average diameter of the inclusions in a continuous casting slab is ～ 18 μm,w hich tends to induce slivers during subsequent cold-rolling process. Experimental in-situ solidification results show that the mushy zone betw een the liquidus and solidus of Fe-Ni alloy is much narrow er than that of plain carbon steel. Stresses are generated during continuous casting,primarily due to the thermal contraction of a few percentage points,and any strain applied to the steel w ithin this temperature region w ill cause cracks to propagate outw ard from the solidification front betw een the dendrites. Numerical simulation results illustrate that heat flux and shell thickness are uneven across the w idth of the mold,particularly the shell thickness close to the edge of the slab surface in the fixed face is 6-mm thinner than that at the slab center. Based on these results,the incidence of surface defects in Fe-Ni alloy can be greatly reduced by the adjustment and optimization of its refining and continuous casting process.

Control on Gradient Adhesive Loading of Porous Laminate:Effects on Multiple Performance of Composites with Bamboo Bundle and Sliver

Elementary units“bamboo bundle”and“bamboo sliver”were processed and cross-linked as“bamboo-bundle veneer(BBV)”and“bamboo-sliver veneer(BSV)”for preparation of laminated composites.The concept of“high-content-adhesive surface treatment”was raised to improve boards’performance,rather than increasing adhesive absorption of every layer’s porous unit.That is,some BBVs experienced an extra“dipping&drying”to absorb more resin(named“HBBV”).The effect of the amount of knitting threads was also discussed for influencing BBV’s quality.Results indicated that light transmittance of BBVs decreased as the amount of threads added from 3 to 8,while mechanical stiffness increased.Adding two skin layers of HBBVs symmetrically was helpful to enhance 24-hour underwater and 28-hour“boil-dry-boil”dimensional stability for boards with BSVs as core,while more than two pairs of HBBVs were needed to improve 28-hour“boil-dry-boil”dimensional stability of boards with BBVs as core.Two symmetrical surface layers of BBVs/HBBVs provided BSV-boards/BBV-boards with greater bending resistance,while such“surface treatment”would not raise shearing strength of BSV-boards upon 28-hour“boil-dry-boil”treatment.Besides,the data obtained from drop-hammer impact test indicated that more than two pair of surface BBVs or HBBVs were required for significant improvement in anti-impact property.

Testing of Cotton Fiber Length

To understand the influences of actual sampling conditions on cotton fiber length testing, this article presents a theoretic study on the distributions and fibrogram of the sample taken out by sampler from ideal sliver at a certain angle. From the distributions expression it can be found that the size of the sampler and the sampling angle are important factors which affect sampling, but if the sampling width is narrow enough, the influence of the sampling angle on the distributions and fibrogram is small enough to be omitted. This is an important conclusion for sampling, in light of this, some suggestions for designing new type sampler are put forward.

Effects of Exogenous Hormone on Fecundity of Sliv-er Fox

The paper aimed to study the effects of exogenous hormone on fecundity of silver fox. Vixens were timely injected with appropriate exogenous hormones at proper ratio to increase their ovulation and litter size, thereby improving the fecundity of silver fox. The average litter size in experimental group attained by 5.86 to 6.0 whelps, 1.61 - 1.75 whelps more than that in the control group. The hormone combination in the experimental group was high in performance/price ratio, which had no significant impact on fecundity of vixens in future.

Impact of the Speed of Flat of a Typical Carding Machine on the Quality of Carded Sliver and 40 Ne Yarn

The carding cycle affects the sliver quality and the subsequent yarn attributes since it is the main sliver formation step. Processing parameters assume a significant part in affecting the nature of the eventual outcome in any sorts of production. In the case of carding machine, a higher production rate makes the operation more sensitive. And this will cause degradation in product quality. So optimization of speed is the talk of the town in spinning field [1]. Extreme higher speed can prompt fiber harm and unnecessary neps generation will corrupt the end result. Again lower speed will lessen the production rate which isn’t reasonable. So we need to discover the ideal speed which will be advantageous to both product quality and production rate. In carding machine, real operational activity happens between flats and cards [1]. From an ordinary perspective, high produce able cards generates higher level of speed. Speed of the cards impacts the carding cycle and the nature of the yarn and in practical point of view, flat’s level of speed is advanced and optimized. The aim of the project was to find out the optimum flat speed in the context of yarn quality. 40 Ne cotton yarns were produced with the slivers manufactured at different flat speeds such as 240, 260, 280, 300 and 320 mm/min. The quality parameters of slivers and yarns were tested and analyzed.

Antibacterial Activity of Silver Nanoparticles Using Salvia officinalis Extract on Some Pathogenic Bacteria

This study included evaluation for the effects of green synthetic nanoparticles of Salvia officinalis aqueous leaf extract loaded with silver nitrate on antibacterial activity. Green synthetic nanoparticles were synthesized by mixing the plant extract with different AgNO3 concentrations (1 mM, 1.5 mM, 1.75 mM, and 2 Mm) then they were detected by color changing and UV visible spectroscopy, which gave indication for the creation of silver nanoparticles. A characteristic and definite surface plasmon resonance (SPR) band for silver nanoparticles was obtained at around 433 nm. The SPR peak of silver nanoparticles extreme peak intensity was obtained at 1.75 mM of AgNO3. Atomic Force Microscopy analysis was used to characterize silver nanoparticles which declared that the shape of green synthetic nanoparticles had different average size depending on sliver concentrations. Since it was observed that the shape and size of green synthetic nanoparticles were concentrations dependent (89.69 nm, 80.94 nm, 76.98 nm and 60.28 nm) respectively for AgNO3 concentrations tested (1 mM, 1.5 mM, 1.75 mM and 2 mM). The antibacterial activity of green synthetic sliver nanoparticles was studied for all G+ve and G-ve selected isolates (Staphylococcus aureus, Staphylococcus heamolytics, Streptococcus pnemoniae, Enterococcus faecalis) and others G-ve bacterial isolates (Escherichi coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa) and the result showed that different green synthetic nanoparticles concentrations (1, 1.5, 1.75, 2 mM) have the ability to inhibit all bacterial isolates with varying zones of inhibition higher than the inhibition observed by ready to use sliver nanoparticles. Minimum inhibitory concentrations (MIC) of green synthetic nanoparticles were obtained in concentration of (31, 27, 23 and 16 μm/mL) for G+ve (S. auerus) and (187, 125, 125, 109 μm/mL) for G-ve (E. coli) at (1, 1.5, 1.75, 2 mM) respectively. The activity of green synthetic sliver nanoparticles in inhibition S. auerus and E. coli, biofilm formation was studied and the result showed that 2 mM nanoparticles could inhibit 75% of S. auerus biofilm and 50% of E. coli biofilm respectively.

Microwave absorption properties of Ag naowires/carbon black composites

The composite that can absorb the high-performance electromagnetic（EM） wave is constructed into a sandwiched structure composed of carbon black（CB）/ethylene-vinyl acetate（EVA） and Ag naowires（Ag NWs）. The Ag NWs sandwiched between two CB/EVA layers are used to improve the absorption properties of composite. The effects of EVA-to-CB weight ratio, concentration and diameter of Ag NWs with a thickness of 0.4 mm on microwave absorption are investigated.The results indicate that for an EVA-to-CB weight ratio of 1：3, Ag NW concentration of 1.0 mg/100 m L, and average diameter of 56 nm, the reflection loss（RL） of the composite is below-10 d B in a frequency range of 9.3 Ghz–18.0 GHz, with the minimum values of-40.0 d B and-25.6 d B at 13.5 GHz and 15.3 GHz, respectively. A finite element method（FEM）is used for calculating the RL of the composite. The calculated results are in agreement with the experimental data.

Radiological evaluation of patellofemoral instability and possible causes of assessment errors:Letter to the editor

This letter to the editor is a commentary on the study titled"Radiological evaluation of patellofemoral instability and possible causes of assessment errors".There are some pertinent structural changes and radiological findings that should be considered in the setting of traumatic knee injuries,as their recognition is of paramount importance.

镗孔精度分析

镗孔精度分析王玉库镗孔一般多用于箱体的孔加工，而箱体是一台机器的基体，它的加工精度的高低直接影响机器的装配精度和使用性能．如何提高箱体孔系的加工精度是箱体零件加工关键．本文着重分析悬臂镗孔时同轴孔系精加工的精度问题．一、箱体零件同轴孔系的分类：大体上...

TE荣获ASPENCORE 2018年度全球电子成就奖

全球连接与传感器领域领军企业TE Conneetivity（TE）今日宣布，凭借行业领先的Sliver SFF-TA-1002连接器，TE荣获ASPENCORE 2018年度全球电子成就奖。该产品具有出色的性能、灵活性和技术创新，以及广泛的行业影响力，被评为“年度高性能无源器件”。

TE Connectivity新型Sliver内部电缆互连产品

TE Connectivity(TE)宣布推出新型Sliver内部电缆互连产品,作为市面上最灵活的解决方案之一,该产品可在电路板上实现内部输入/输出(I/O)连接。这项新技术无需使用复位定时器以及价格高昂的低损耗印刷电路板(PCB)材料,从而可简化设计流程,有助于降低整体成本。新款Sliver互连产品采用TE高速电缆,其数据传输速度最高可达每秒25千兆位(Gbps)。TE Connectivity数据与终端设备事业部产品经理Melissa Knox表示:'我们全新推出的Sliver内部电缆互连系统已受到我们首批客户的热烈追捧。