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Systematic study on the microstructural evolution, interfacial diffusion and mechanical properties of ultra-thin stainless steel–copper composites (50 µm) after annealing treatment was conducted in the present study. The results show that the as-received specimen exhibits low elongation (0.031) as well as high strength (891.346 MPa) by work hardening, thus requires heat treatment to improve the plasticity. With the increase of annealing temperature from 700 to 1000 °C, the dislocation/grain boundary strengthening is weakened while the surface grains which exhibit fewer constraints is increasing, resulting in lower strength. Moreover, a uniform and refined microstructure with high recrystallization rate is formed inside stainless steel and copper matrixes for the specimens annealed at 900 °C, thereby improving the plasticity of ultra-thin stainless steel–copper composites. Additionally, an obvious strain gradient exists at the interface of ultra-thin stainless steel–copper composites, and the interdiffusion process between stainless steel and copper matrixes is primarily governed by the diffusion of Cu atoms. The influence of diffusion layer thickness on the strength of ultra-thin stainless steel–copper composites is negligible. Overall, an optimal annealing temperature of 900 °C is obtained with the improved plasticity of ultra-thin stainless steel–copper composites. [ABSTRACT FROM AUTHOR]

The tribological behavior of traditional oil-in-water (O/W) lubricants (1.0 wt.%) and nano-TiO2 additive lubricants (1.0–9.0 wt.%) during micro rolling of titanium foils were analyzed. In this study, the surface morphologies of titanium foils under various lubrication conditions were assessed, and the corresponding lubrication mechanisms were revealed. The tribological behavior of nano-TiO2 additive lubricants during micro rolling of titanium foils was also explored through a series of characterization methods. The utilization of nano-TiO2 additive lubricants in micro rolling reduces the surface roughness of titanium foils. Moreover, it effectively inhibits the generation of indentations and cracks during rolling processes, enhancing the surface quality of rolled specimens. Additionally, owing to the synergism of rolling, tribo-film, mending and polishing effects of the nanoparticles, both the rolling force and surface roughness were minimized by using lubricants containing 3.0 wt.% TiO2 nanoparticles. Overall, an optimal concentration (3.0 wt.%) of TiO2 nanoparticles in water-based nanolubricants was obtained with enhanced tribological properties and lubrication performance during micro rolling of titanium foils. [ABSTRACT FROM AUTHOR]

TiSiCN composite coatings with different C contents were prepared on Cr buffer layer by plasma‐enhanced magnetron sputtering. The structure, composition, surface, and cross‐sectional morphology of the coatings were characterized by X‐ray photoelectron spectroscopy, X‐ray diffraction, Raman spectroscopy, scanning electron microscope, and atomic force microscope. The hardness, elastic modulus, and tribological performance of the coatings were evaluated by nanoindentation and reciprocating friction tests. The results showed that the TiSiCN composite coatings are amorphous structure composed of TiCN compound and microcrystalline graphite, and amorphous phases. The increase of C content changed the content and distribution of TiCN ceramics nanocrystal, amorphous Si3N4 and amorphous carbon (sp3‐ and sp2‐hybridized C), thus affecting the hardness and friction behavior of the coatings. The hardness of the composite coatings was related to the content of TiCN phase and sp3‐C in the coatings. The TiSiCN composite coating with C content of 68.2% had lower coefficient of friction and the lowest wear rate. [ABSTRACT FROM AUTHOR]

Corrugated rolling is one of the metal forming processes using corrugated rolls to machine hard-to-deform metals, which leads to problems of high friction and severe wear. Lubricants are essential to reduce rolling forces, extend the life of corrugated rolls, and improve efficiency. In this work, a comparison of the surface quality of copper plates after corrugated rolling adopting different lubrication conditions (dry condition, O/W lubricant, TiO2 water-based nanolubricants) was made to explore the tribological behavior and lubricant mechanism of water-based nanolubricant during the corrugated rolling of copper plates. The results show that the 3.0 wt.% water-based nanolubricant exhibits excellent lubrication performance, and the maximum rolling force is reduced by 21.49% compared with the dry condition. Additionally, the effect of reduction on the surface quality of corrugated rolled copper plates was explored. The surface roughness at the peak position of the copper plate increased gradually with increasing reduction, and the surface roughness at the trough position showed little change, which was mainly caused by the synergistic effect of the roughness transfer and the high-strain hardening at the trough position of the copper plate. Overall, an optimal concentration of 3.0 wt.% water-based nanolubricant exhibits the best properties in terms of reducing the rolling forces and improving the surface quality of the rolled copper plates during corrugated rolling processes. [ABSTRACT FROM AUTHOR]

During past decades, water-based and oil-in-water (O/W) based nanolubricants with nanoparticles (NPs) as additives have been developed to replace conventional oil-based lubricants for solving contamination problems during rolling processes. The formulations of nanolubricants for rolling need to be continuously improved to provide better lubrication performance. This article reviews the formulation, physicochemical properties, and lubrication mechanisms during rolling with water-based and O/W based nanolubricants, and the effects of nanolubricants on rolling force, surface roughness and oxide skin formation during rolling are discussed. This review aims to facilitate the fundamental understanding of nanolubrication and the development of rolling lubrication technology. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman spectroscopy (SERS) can boost the pristine Raman signal significantly which could be exploited for producing innovative sensing devices with advanced properties. However, the inherent complexity of SERS systems restricts their further applications in rapid detection, especially in situ detection in narrow areas. Here, we construct an efficient and flexible SERS-based Lab-on-Fiber (LOF) sensor by integrating Ag/Au nanocap arrays obtained by Ag/Au coating polystyrene nanospheres on the optical fiber face. We obtain rich "hot spots" at the nanogaps between neighboring nanocaps, and further achieve SERS performance with the assistance of laser-induced thermophoresis on the metal film that can achieve efficiency aggregation of detected molecules. We achieve a high Raman enhancement with a low detection limitation of 10−7 mol/L for the most efficient samples based on the above sensor. This sensor also exhibits good repeatability and stability under multiple detections, revealing the potential application for in situ detection based on the reflexivity of the optical fiber. [ABSTRACT FROM AUTHOR]

In this work, an experimental investigation on the lubrication performance of water-based nanolubricant with TiO2 as nanoadditives was performed. The nanolubricants show excellent dispersibility and stability within 5 days after preparation. Additionally, the results show that the concentration of TiO2 nanoparticles significantly affects the lubrication performance of the prepared nanolubricant during microrolling. The excessive nanoparticles lead to agglomeration at the contact area, while the limited nanoparticles can hardly work during rolling processes. Instead, for a nanolubricant with 3.0 wt% of TiO2 nanoparticles, the nanolubricant is able to feed abundant nanoparticles continuously to the rubbing zone with little agglomeration, improving the surface quality of copper foils during microrolling. [ABSTRACT FROM AUTHOR]

In this study, the effect of cold rolling reduction ratio (CRRR) on the microstructure and mechanical properties of ferritic stainless steel (FSS) 430 were analyzed based on a series of experiments. The results show that the thickness of coarse grain bands decreases with an increase in CRRR, and when the CRRR increases to a certain value, the coarse grain bands break down into refined, equiaxed grains due to the plastic deformation. In addition, the optimization of CRRR was found to benefit both the microstructural refinement and mechanical properties of FSS 430. Also, the optimization of CRRR optimized the texture structure of FSS 430 by reducing the fraction of undesired components ({110} < 110 > component, for example), giving a rise to the plasticity of material. On the other hand, the formation of Lüders band can also be affected by the modification of CRRR. Overall, an optimal CRRR of 70% was obtained with refined microstructure and texture structure, thereby improving the mechanical properties of FSS 430. [ABSTRACT FROM AUTHOR]

In the present work, a comparison between traditional oil‐in‐water (O/W) based lubricant and nano‐TiO2 additive water‐based lubricants was made to explore the lubrication effects during rolling of ferritic stainless steel (FSS) strips. The results show that marked reduction in rolling force and improvement in the surface quality can be achieved by utilisation of water‐based nanolubricant, which can be attributed to the synergism of rolling effect, mending effect, polishing effect and protection film. An optimal concentration of 3.0 wt% TiO2 nanoparticles is found to exhibit excellent lubrication effects with sufficient nanoparticles at real contact regions without aggregation, leading to 10% reduction in the surface roughness during rolling of FSS strips. [ABSTRACT FROM AUTHOR]

Water-based nanolubricants with different concentrations of TiO2 nanoparticles were prepared and the wettability and viscosity were evaluated. The results show that the addition of TiO2 nanoparticles improves the lubrication performance during microrolling of ultrathin stainless steel foils. In addition, the viscosity decreases dramatically with the increase in the concentration of nanoparticles, which was related to the change of dispersing agent concentration. Microrolling tests were performed to explore the lubrication conditions during microrolling of ultrathin stainless-steel strips, and the results showed that the refined surface quality of the rolled strips was achieved with 3.0 wt% TiO2. The improvement in surface quality can be attributed to the synergism of the rolling effect, polishing effect, protection film, and mending effect of TiO2 nanoparticles. [ABSTRACT FROM AUTHOR]

Systematic study on the microstructural evolution and mechanical properties of ferritic stainless steel (FSS) 430 with different annealing processes was carried out in the present work. The results show that microstructural refinement can be achieved by optimization of annealing processes, improving elongation, yield strength, and tensile strength of FSS 430. An optimal annealing temperature of 950 ℃ is found with better homogeneity and enhanced mechanical properties among the cold-rolled and annealed FSSs. During annealing processes, the fraction of high-angle grain boundaries of FSS 430 annealed at 950 ℃ is found to be the highest, indicating that a homogeneous microstructure with high recrystallization rate is formed inside the FSS 430 strips. In addition, high fraction of the hard grains (SF < 0.4) and low fraction of the soft grains are found inside FSS 430 annealed at 950 ℃, improving the plasticity of material. Overall, the optimization of annealing processes benefits the microstructural refinement of FSS and thereby improving the mechanical properties of materials. [ABSTRACT FROM AUTHOR]

Water-based lubricants with different fractions of TiO2 nanoparticles ranging from 1.0 to 9.0 wt.% were utilized to study the lubrication mechanisms during micro rolling tests and the tribological behaviour of nanolubricants during the micro rolling of copper foils. The results indicate that the application of TiO2 nanolubricants remarkably improves the surface quality of rolled copper foils during rolling processes. For lubricants with inadequate TiO2 nanoparticles, it is found that few TiO2 nanoparticles enter the contact regions between the rolls and foils, causing insufficient lubrication during rolling processes. Instead, for lubricants with excessive TiO2 nanoparticles, obvious agglomeration occurs at the contact regions and promotes the generation of voids on the surface of the rolled foils, thereby deteriorating the surface quality of the rolled copper foils. In addition, it is found that the surface quality of rolled foils is improved by utilizing a large reduction ratio. Overall, the fraction of 3.0 wt.% TiO2 nanolubricants is optimal to improve the lubrication conditions at the contact regions, thereby improving the surface quality of the rolled copper foils. [ABSTRACT FROM AUTHOR]

In this article, the horizontal hinged heavy duty servo cylinder is taken as the research object. In the actual working process, while the servo hydraulic cylinder outputs the curve force, the cylinder body will also rotate with the hinge point to a certain extent. Because the position of the center of gravity is constantly changing, and the weight of the cylinder body is too large, the friction causes damage to the sealing structure and seriously affects the working efficiency of the equipment. In order to improve the sealing performance of the servo hydraulic cylinder, a corresponding study is carried out. Firstly, the working angle interval of servo cylinder is optimized to ensure that the friction is the least in this range. Based on this, a new supporting structure is proposed, in which a small hydraulic cylinder is installed at the bottom of the servo hydraulic cylinder body. By controlling the output force of the small hydraulic cylinder, the cylinder body and piston rod are aligned all the time. The servo cylinder body is flexibly processed to more realistically see the adverse effect of the friction, and the co-simulation method using MSC.ADAMS and MATLAB/Simulink verifies the new support structure to improve the sealing performance. According to the simulation results and experiment results, and combined with the deformation curve of the hydraulic cylinder, when the maximum displacement is 336 mm, the maximum rotation angle is 15.6°, the friction is the smallest, about 5801.9 N. It is known from the experiment results that after adding the new support structure, the frictional force is reduced to 1365.9 N, which reduces the friction of nearly 76.5%. [ABSTRACT FROM AUTHOR]

Concurrent indoor–outdoor fine particulate matter (PM2.5) measurements were conducted at urban, suburban, and rural sites in Harbin, a megacity in the northeast of China. Chemical constituents of indoor–outdoor PM2.5 were determined. Infiltration factors (FINF) of all sites were calculated according to the indoor to outdoor (I/O) ratios of PM2.5 based on the regression analysis. Linear discriminant analysis (LDA) is applied to determine the indoor–outdoor relationship. Secondary organic carbon (SOC) was calculated on the basis of organic carbon to elemental carbon (OC/EC) ratios. The mean concentrations of indoor and outdoor PM2.5 were 166.4 ± 32.5 μg/m3 and 228.4 ± 83.7 μg/m3, respectively, during the heating period. OC/EC and potassium ion to elemental carbon (K+/EC) ratios verified that biomass was an important source in Harbin especially for rural sites. The nitrate to sulfate (NO3−/SO42−) ratio indicates the higher contribution of traffic emissions in urban sites. Cr was the only species that exceeded the guidelines of WHO 2002, which was mainly emitted from coal and oil combustion. SOC/OC and NO3−/SO42− ratios, and ion-balanced acidity (the ratio of cation to anion, R+/−) showed a large urban–rural and indoor–outdoor difference. The highest SOC/OC ratio was found at urban sites, up to 38.3% for indoors. SOC/OC ratios and R+/− values of indoor environments were higher, which is attributed to the conducive condition of forming the secondary pollutants during the heating period. The results of LDA indicated that the distributions of the chemical components of PM2.5 at three sites were statistically dissimilar. [ABSTRACT FROM AUTHOR]

We report on the continuous-wave and passively Q-switched waveguide laser at the wavelength of ∼1024 nm, based on the (Yb0.1Y0.9)3(Sc1.5Ga0.5)Ga3O12 (Yb:YSGG) crystal. The ridged waveguide was fabricated on the surface of 100 at% Yb:YSGG crystal by the swift ion irradiation and the precise diamond blade dicing. Utilizing this waveguide as the gain medium and resonant cavity, the laser emission at ∼1024 nm was realized. Coating the tungsten disulfide onto the waveguide surface as the saturable absorber, the Q-switched laser emission was also obtained with the pulse duration of 125 ns. [ABSTRACT FROM PUBLISHER]

Few studies have examined the quality of life (QOL) in survivors of non-Hodgkin lymphoma (NHL). A total of 109 patients with NHL (58 aggressive [AGG], 51 indolent [IND]) completed two health-related QOL assessments using the Medical Outcomes Study 36-Item Short-Form Healthy Survey (MOS SF-36) and the Functional Assessment in Cancer Therapy - Fatigue (FACT-F). Scores between IND and AGG were compared using a two-sample t-test. Multiple linear regression was performed to account for any potentially explanatory variables. Overall, 70.6% had received chemotherapy and 55% had received immunotherapy. Some 17.6% of the IND group had received no therapy. The overall physical and mental component QOL scores of the SF-36 did not differ between survivors. Physical function in survivors of IND was significantly better when compared with that of AGG NHL. Our study reports a similar overall QOL between survivors of IND and AGG NHL. Physical function, however, may be more impaired in survivors of AGG NHL. [ABSTRACT FROM AUTHOR]

In previous studies, we reported that indole-3-carbinol (I3C) and myo-inositol (MI) inhibit lung adenoma induced by tobacco smoke carcinogens in A/J mice. In this paper, we extended our work and examined the effects of I3C (70 or 30 μmol/g diet) and MI (56 μmol/g diet) against vinyl carbamate (VC)-induced lung adenocarcinoma by administering the agents from 1 week after the second of two injections of VC until termination of the study at week 18. The higher dose of I3C decreased multiplicities of tumors on the surface of the lung (26%, P = 0.0005), carcinoma incidence (38%), multiplicity (67%, P < 0.0001) and size (complete abolition of carcinoma with an area of >1.0 cm2) as well as adenoma with cellular pleomorphism (46%, P < 0.0001). The lower dose of I3C was less effective. MI decreased multiplicities of pulmonary surface tumors (20%, P = 0.0005), adenoma with cellular pleomorphism (40%, P < 0.0001) and lung adenoma (52%, P < 0.0001) and the proportion of the biggest carcinoma (carcinoma with an area of >1.0 cm2, P < 0.05). Immunoblot analyses of lung tissues for potential target identification showed that I3C (70 μmol/g diet) inhibits IkappaBα degradation, nuclear factor-kappaB activation, expression of cyclooxygenase-2, phospho-Akt and fatty acid synthase (FAS) and activates caspase-3 and poly ADP ribose polymerase cleavage. The effect of MI was limited to inhibition of phospho-Akt and FAS expression. Our data show that I3C and MI inhibit lung carcinoma and provide a basis for future evaluation of these compounds in clinical trials as chemopreventive agents for current and former smokers. [ABSTRACT FROM PUBLISHER]

When an output curve force is applied to a horizontal servo cylinder with a heavy load, the piston rod bears a dynamic partial load based on the installation and load characteristics, which significantly affects the frequency response and control accuracy of the servo cylinder. Based on this partial load, increased friction can lead to cylinder bore scuffing, leakage, lack of output power, or even system failure. In this paper, a novel asymmetric static-pressure support structure is proposed based on the principle of hydrostatic support. The radial component force of a dynamic partial load is balanced by cooperation between the support oil cushion of the variable hydraulic pressure support structure, oil cushion of the supportive force, and the damper. Adaptive control of the servo cylinder piston rod, guide sleeve, and piston, as well as the cylinder oil film friction between lubricated surfaces is achieved. In this paper, theoretical design and analysis of the traditional hydrostatic bearing structure and novel structure are presented. A hydraulic dynamic shear scissor is used as a research target to derive a structural dynamic model. Comparative simulations are performed using Matlab Simulink. Additionally, flow field analysis of the novel structure is performed, which verifies the rationality and feasibility of the proposed structure and system. [ABSTRACT FROM AUTHOR]

We demonstrate a tunable hybrid Graphene-Nd:YAG cladding waveguide laser exploiting the electro-optic and the Joule heating effects of Graphene. A cladding Nd:YAG waveguide was fabricated by the ion irradiation. The multi-layer graphene were transferred onto the waveguide surface as the saturable absorber to get the Q-switched pulsed laser oscillation in the waveguide. Composing with appropriate electrodes, graphene based capacitance and heater were formed on the surface of the Nd:YAG waveguide. Through electrical control of graphene, the state of the hybrid waveguide laser was turned on or off. And the laser operation of the hybrid waveguide was electrically tuned between the continuous wave laser and the nanosecond pulsed laser. [ABSTRACT FROM AUTHOR]

The article presents the results of a case study on the relationship between diabetes and infectious hospitalizations in renal transplant recipients. The outcome of interest was infection requiring hospitalization occurring in the posttransplant period. The survival time until development of hospital infections was analyzed using Cox multivariate proportional hazard models. The study found that a greater proportion of PreTDM and PostTDM patients had infections after transplantation compared with NonDM patients.