Optimizing Row Spacing to Ameliorate the Productivity of Spring Sugarcane (Saccharum officinarum L.)

One of the main reasons behind reduced cane yield is pathetic method of planting. Planting method and row spacing are the most important yield contributing factors in sugarcane. A field experiment was carried out in order to determine quality and yield of sugarcane in various spatial arrangements. Treatments are 180 cm spaced trenches with triple row strips;180 cm spaced trenches with alternate row strips;120 cm spaced trenches with double row strips and 60 cm spaced furrow with single row. Perusal of data revealed that 3.6%, 13.4%, 15%, 15.3% more cane diameter (cm), cane length (cm), stripped cane yield (t·haˉ1), sugar yield (t·haˉ1) were obtained from 180 cm spaced trenches with triple row strips as compared to conventional planting method i.e. 60 cm spaced furrows. While the number of millable canes mˉ2, polarity %, cane juice purity %, cane juice %, commercial cane sugar % and cane sugar recovery % remained non-significant by different planting techniques.

Non-Newtonian biomagnetic fluid flow through a stenosed bifurcated artery with a slip boundary condition

The effects of a velocity slip and an external magnetic field on the flow of biomagnetic fluid(blood)through a stenosed bifurcated artery are investigated by using ANSYS FLUENT.Blood is regarded as a non-Newtonian power-law fluid,and the magnetization and electrical conductivity are considered in the mathematical model.The no-slip condition is replaced by the first-order slip condition.The slip boundary condition and magnetic force are compiled in the solver by the user-defined function(UDF).Numerical solutions are obtained by the finite volume method based on a nonuniform grid structure.The accuracy and efficiency of the solver are verified through a comparison with the literature.The results are presented graphically for different parameter values,and the effects of the magnetic number,the magnetic source position,the vascular obstruction ratio,the slip parameter,and the power-law index on the flow and temperature fields are illustrated.

Fast strength-ductility synergistically adjusting of cold spray additive manufactured Cu deposits via electric pulse processing

Electric Pulse Processing(EPP)treatment was innovatively introduced to optimize the strength and ductility of the CSAMed Cu deposits.The results show that EPP is an efficient and fast post-treatment to improve the strength and ductility(within tens of seconds).The larger the pulse current and number of pulses,the better the mechanical properties.Interestingly,this research found that when the heat input determined by pulse current and number of pulses exceeds a certain threshold(pulse current intensity is 2000 A,number of pulses is 10),increasing the number of repeat time could also effectively improve the mechanical properties.A tensile strength of 210 MPa and a ductility of 14.0%could be obtained with reasonable EPP parameters(pulse current intensity is 2000 A,number of pulses is 10,and repeat number is 2),which is similar to those of conventional annealing(e.g.,tensile strength is 272 MPa,elongation is 28.3%).The microstructure evolution analysis shows that EPP can effectively improve the bonding quality between the deposited particles by recrystallization,promote grain growth and the formation of twins,which is the main reason for the improvement of mechanical properties.

基于层次结构的隐私多维分析查询算法

基于本地化差分隐私的多维分析查询(multi-dimensional analytical query,MDA)已得到了研究者的广泛关注.现有基于最优局部哈希(optimal local Hashing,OLH)机制与层次树结构的扰动方法存在泄露根结点隐私的风险.针对现有结合层次树结构的本地扰动机制不足,提出了一种有效且满足本地化差分隐私的MDA查询算法H4MDA (hierarchical structure for MDA),该算法充分利用层次树的横向与纵向结构特征设计了3种基于用户分组策略的本地扰动算法HGRR,LGRR-FD,LGRR.算法HGRR结合层次树横向结构与GRR机制本地扰动用户元组数据,通过摈弃根结点组合来响应MDA查询.不同于HGRR,LGRR-FD算法利用层次树的纵向结构与GRR机制扰动本地数据,同时通过添加假数据来避免叶子结点的隐私泄露.LGRR算法通过摈弃叶子结点层纵向扰动本地数据.收集者结合LGRR的扰动结果利用局部一致性处理技术重构层次树最后两层,通过添加虚拟叶子结点来响应MDA查询,而虚拟叶子结点计数之和等于其父节点计数.HGRR,LGRR-FD,LGRR算法与现有扰动算法在3种数据集上实验结果表明,其响应MDA查询的精度优于同类算法.

CLIP170通过TGF-β通路抑制甲状腺乳头状癌的转移

目的:研究细胞质连接蛋白170(cytoplasmic linker protein 170,CLIP170)是否影响甲状腺乳头状癌(papillary thyroid cancer,PTC)细胞的转移和侵袭并阐明其机制。方法:通过GEO和TCGA数据分析CLIP170在PTC中的表达水平;通过慢病毒转染技术构建CLIP170敲减细胞,Transwell转移和侵袭实验评估其功能;通过免疫荧光观察CLIP170对细胞肌动蛋白结构的影响;以ELISA方法检测细胞培养基中转化生长因子-β(transforming growth factor-β,TGF-β)1的释放;通过免疫印迹和实时定量荧光PCR方法检测上皮-间充质转化(epithelial-mesenchymal transition,EMT)和TGF-β信号通路分子的表达量并最终在裸鼠肺转移模型中验证。结果:CLIP170在PTC中的表达量比在正常甲状腺组织中的表达量低。功能方面,CLIP170KD在体外和体内均显著增强了PTC细胞的转移;机制方面,CLIP170KD触发了TGF-β通路的激活,促进肿瘤细胞的迁移和侵袭。TGF-β的抑制剂有效抑制了TGF-β活性,并显著逆转CLIP170KD所诱导的肿瘤转移。结论:CLIP170有望成为一种缓解有转移倾向的PTC的治疗靶点。

Deposition of FeCoNiCrMn high entropy alloy(HEA) coating via cold spraying

High entropy alloys(HEAs) are of great interest in the community of materials science and engineering due to their unique phase structure. They are constructed with five or more principal alloying elements in equimolar or near-equimolar ratio. Therefore, HEAs can derive their performance from multiple principal elements rather than a single element. In this work, solid-state cold spraying(CS) was applied for the first time to produce FeCoNiCrMn HEA coating. The experimental results confirm that CS can be used to produce a thick HEA coating with low porosity. As a low-temperature deposition process, CS completely retained the HEA phase structure in the coating without any phase transformation. The characterization also reveals that the grains in the CSed HEA coating had experienced significant refinement as compared to those in the as-received HEA powder due the occurrence of dynamic recrystallization at the highly deformed interparticle region. Due to the increased dislocation density and grain boundaries,CSed HEA coating was much harder than the as-received powder. The tribological study shows that the CSed FeCoNiCrMn HEA coating resulted in lower wear rate than laser cladded HEA coatings.

Characterizations and anisotropy of cold-spraying additive-manufactured copper bulk

In this study, thick copper coatings were deposited by cold spraying（CS） as an additive manufacturing（AM） method. The interfacial microstructure evolution and mechanical behavior were investigated for the as-sprayed and annealed conditions. In addition, experiments together with numerical simulations were employed to study the recrystallization in different stages. Finally, the mechanical anisotropy of the CSed deposit was tested for the first time, being important to the applications of CS-AM. Results show that there exist two stages of recrystallization in the spraying and annealing processes. Heat treatment has a significant effect on mechanical properties, i.e., the tensile strength increases by 34.2% while microhardness decreases by 43.6%. The mechanical anisotropy analysis shows that the tensile strengths of different directions are completely different and show some regular changes.

Optimization of cold-sprayed AA2024/Al_2O_3 metal matrix composites via friction stir processing: Effect of rotation speeds

In this study, friction stir processing（FSP） was employed to modify cold-sprayed（CSed） AA2024/Al2 O3 metal matrix composites（MMCs）. Three different rotation speeds with a constant traverse speed were used for FSP. Microstructural analysis of the FSPed specimens reveals significant Al2 O3 particle refinement and improved particle distribution over the as-sprayed deposits. After FSP, a microstructural and mechanical gradient MMC through the thickness direction was obtained. Therefore, a hybrid technique combining these two solid-state processes, i.e. CS and FSP, was proposed to produce functionally gradient deposits. The Guinier-Preston-Bagaryatskii zone was dissolved during FSP, while the amounts at different rotation speeds were approximately the same, which is possibly due to the excellent thermal conductivity of the used Cu substrate. Mechanical property tests confirm that FSP can effectively improve the tensile performance and Vickers hardness of CSed AA2024/Al2 O3 MMCs. The properties can be further enhanced with a larger rotation speed with a maximum increase of 25.9% in ultimate tensile strength and27.4% in elongation at 1500 rpm. Friction tests show that FSP decreases the wear resistance of CSed MMCs deposits due to the breakup of Al2 O3 particles. The average values and fluctuations of friction coefficients at different rotation speeds vary significantly.

Hot deformation behavior and microstructure evolution of the laser solid formed TC4 titanium alloy

Hot compressive experiments of the laser solid formed(LSFed)TC4 titanium alloy were conducted at a wide temperature range of 650-950℃and strain rate of 0.01-10 s^(-1).The Arrheniustype constitutive models of the LSFed TC4 alloy were established at the temperature range of 800-950℃and of 650-800℃,respectively.The average relative error between the predicted stresses and experimental values in those two temperature ranges are 10.4%and 8.3%,respectively,indicating that the prediction models constructed in this paper are in a good agreement with experimental data.Processing maps were established by the principle of dynamic materials modeling on the basis of the data achieved from the hot compression experiments.The processing parameters corresponding to the stable and unstable regions of material deformation can be determined from the processing maps.The microstructure evolution of the stable and unstable regions of the samples after tests were observed.Finally,the effect of hot compressive parameters on the microstructure were investigated to research the dynamic recrystallization and the texture of the deformed LSFed TC4 alloy.

Electrochemical characterization and microstructure of cold sprayed AA5083/Al_(2)O_(3) composite coatings

This work focused on the role of Al_(2)O_(3) particles in the corrosion behavior of cold sprayed AA5083 aluminum alloy matrix composite(Al-MMC)coatings.The electrochemical characterization of the coatings was investigated in a 3.5 wt.%NaCl solution as a function of time.The results show that fragmentation of Al_(2)O_(3) particles is not clearly observed in the case of AA5083/20 vol.%Al_(2)O_(3) coating,while the broken Al_(2)O_(3) particles can be seen clearly in AA5083/40 vol.%Al_(2)O_(3) and AA5083/60 vol.%Al_(2)O_(3) coatings.The addition of 20 vol.%Al_(2)O_(3) particles yield the coating with the lowest porosity,and different volume fractions of Al_(2)O_(3)in the feedstock have important effects on the electrochemical behavior of composite coatings.The Al-MMC coating reinforced with 20 vol.%Al_(2)O_(3) particles exhibits the highest Ecorrand the lowest icorrcompared with the other conditions.The order of current density is as follows:AA5083/20vol.%Al_(2)O_(3)<AA5083<AA5083/40 vol.%Al_(2)O_(3)<AA5083/60 vol.%Al_(2)O_(3).

Solid-state additive manufacturing and repairing by cold spraying:A review

High-performance metal additive manufacturing （AM） has been extensively investigated in recent years because of its unique advantages over traditional manufacturing processes. AM has been applied to form complex components of Ti, Fe or Ni alloys. However, for other nonferrous alloys such as AI alloys, Mg alloys and Cu alloys, AM may not be appropriate because of its melting nature during processing by laser, electron beam, and/or arc. Cold spraying （CS） has been widely accepted as a promising solid-state coating technique in last decade for its mass production of high-quality metals and alloys, and/or metal matrix composites coatings. It is now recognized as a useful and powerful tool for AM, but the related research work has just started. This review summarized the literature on the state-of-the-art and problems for CS as an AM and repairing technique.

Solid-state cold spraying of FeCoCrNiMn high-entropy alloy:an insight into microstructure evolution and oxidation behavior at 700-900℃

About 3 mm thick five-element equimolar high-entropy alloy(HEA) FeCoCrNiMn was successfully deposited by solid-state cold spraying(CS).The high-temperature oxidation behavior of the CSed HEA was investigated at 700-900℃.Heat treatment was performed on the CSed HEA before oxidation to heal the incomplete interfaces between the deposited particles.Results show that the microstructure of the CSed HEA is characterized by grain refinement and abundant interparticle incomplete interfaces.Post-spray heat treatment promotes recrystallization and grain growth in the CSed HEA.After oxidation testing,the oxide scales are composed of multi-layers:a Mn_(2)O_(3)(or Mn_(3)O_(4)) outer layer,a Mn-Cr spinel intermediate layer and a Cr_(2)O_(3) inner layer.The CSed HEA exhibits higher parabolic rate constants and more favorable internal oxidation than the bulk HEAs that have similar compositions in the literature.Such a discrepancy becomes pronounced at higher temperatures.The grain refinement and numerous particle boundaries are responsible for such a distinctive performance of the CSed HEA.