Dual-functional marigold-like Zn_(x)Cd_(1-x)S homojunction for selective glucose photoreforming with remarkable H_(2)coproduction

The global commitment to pivoting to sustainable energy and products calls for technology development to utilize solar energy for hydrogen(H_(2))and value-added chemicals production by biomass photoreforming.Herein,a novel dual-functional marigold-like Zn_(x)Cd_(1-x)S homojunction has been the production of lactic acid with high-yield and H_(2)with high-efficiency by selective glucose photoreforming.The optimized Zn_(0.3)Cd_(0.7)S exhibits outstanding H_(2)generation(13.64 mmol h^(-1)g^(-1)),glucose conversion(96.40%),and lactic acid yield(76.80%),over 272.80 and 19.21 times higher than that of bare ZnS(0.05 mmol h^(-1)g^(-1))and CdS(0.71 mmol h^(-1)g^(-1))in H_(2)generation,respectively.The marigold-like morphology provides abundant active sites and sufficient substrates accessibility for the photocatalyst,while the specific role of the homojunction formed by hexagonal wurtzite(WZ)and cubic zinc blende(ZB)in photoreforming biomass has been demonstrated by density functional theory(DFT)calculations.Glucose is converted to lactic acid on the WZ surface of Zn_(0.3)Cd_(0.7)S via the photoactive species·O_(2)^(-),while the H_(2)is evolved from protons(H^(+))in H_(2)O on the ZB surface of Zn_(0.3)Cd_(0.7)S.This work paves a promising road for the production of sustainable energy and products by integrating photocatalysis and biorefine.

Nondestructive Determination of Cu Residue in Orange Peel by Laser Induced Breakdown Spectroscopy

Laser induced breakdown spectroscopy （LIBS） is an emerging tool with rapid, nondestructive, green characteristics in qualitative or quantitative analyses of composition in materials. But LIBS has its shortcomings in detect limit and sensitivity. In this work, heavy metal Cu in Gannan Navel Orange, which is one of famous fruits from Jiangxi of China, was analyzed. In view of LIBS＇s limit, it is difficult to determinate heavy metals in natural fruits. In this work, nine orange samples were pretreated in 50-500 μg/mL Cu solution, respectively. Another one orange sample was chosen as a control group without any pollution treatment. Previous researchers ob- served that the content of heavy metals is much higher in peel than in pulp. So, the content in pulp can be reflected by detecting peel. The real concentrations of Cu in peels were acquired by atomic absorption spectrophotometer （AAS）. A calibration model of Cu I 324.7 and Cu I 327.4 was constructed between LIBS intensity and AAS concentration by six samples. The correlation coefficient of the two models is also 0.95. All of the samples were used to verify the accuracy of the model. The results show that the relative error （RE） between predicted and real concentration is less than 6.5%, and Cu I 324.7 line has smaller RE than Cu I 327.4. The analysis demonstrated that different characteristic lines decided different accuracy. The results prove the feasibility of detecting heavy metals in fruits by LIBS. But the results are limited in treated samples. The next work will focus on direct analysis of heavy metals in natural fruits without any pretreatment. This work is helpful to explore the distribution of heavy metals between pulp and peel.

Free energy calculation of single molecular interaction using Jarzynski's identity method:the case of HIV-1 protease inhibitor system

Jarzynski＇ identity （JI） method was suggested a promising tool for reconstructing free energy landscape of biomolecular interactions in numerical simulations and ex- periments. However, JI method has not yet been well tested in complex systems such as ligand-receptor molecular pairs. In this paper, we applied a huge number of steered molec- ular dynamics （SMD） simulations to dissociate the protease of human immunodeficiency type I virus （HIV-1 protease） and its inhibitors. We showed that because of intrinsic com- plexity of the ligand-receptor system, the energy barrier pre- dicted by JI method at high pulling rates is much higher than experimental results. However, with a slower pulling rate and fewer switch times of simulations, the predictions of JI method can approach to the experiments. These results sug- gested that the JI method is more appropriate for reconstruct- ing free energy landscape using the data taken from experi- ments, since the pulling rates used in experiments are often much slower than those in SMD simulations. Furthermore, we showed that a higher loading stiffness can produce higher precision of calculation of energy landscape because it yields a lower mean value and narrower bandwidth of work distri- bution in SMD simulations.

Preparation and Characterization Analysis of Hydroxyapatite/ Gelatin Composite

The hydroxyapatite （ HAp ）/gelatin composite was prepared by self-assembly method. X-ray diffraction confirmed that the inorganic phase in the composite was HAp. The Fourier transform infra-red spectrum （FT-IR） indicated the presence of amide and hydroxyl groups in the composite. The organic-inorganic ratio of the composite is similar to that of the human bone, which was determined by differential thermal analysis （ DTA ） and thermogravimetric analysis （ TGA ）. Transmission Electron Microscopy （TEM） showed that the composite is composed by spindly grains and the rmdtilayer nanostructure can also be seen. Gelatin in the composite assembled orderly and orderly and directionally ; and the HAp crystals grew along the gelatin molecule at nearly the same direction. A model was established to explain the process of the interaction between gelatin and HAp.

Cell traction force distribution and its implications in cell adhesion and migration

Cell-matrix interaction is the key for understanding the cell behaviors,especially the mechanosensitivity of cell adhesion,cell migration and differentiation,etc.Cells are constantly probing,pushing and pulling on the surrounding extracellular matrix.These cell-generated forces drive cell migration and tissue morphogenesis,and maintain the intrinsic mechanical tone of tissues.Therefore,knowledge of the spatial and temporal nature of these forces are essential to understanding when and where mechanical events come to play in both physiological and pathological settings.However,because of the complexity of cell geometry and insufficient

A surface-modified biodegradable urethral scaffold seeded with urethral epithelial cells

Background Efficient cell adhesion and proliferation is a central issue in cell-based tissue engineering, which offers great promise for repair of urethral defects or strictures. This study evaluated the adhesion and growth of rabbit uroepithelium on a surface-modified three-dimensional poly-L-lactic acid （PLLA） scaffold.Methods Urethral mucosa were harvested from male New Zealand rabbits and the urothelium were dissociated and then cultured. Immunocytochemistry on cultured uroepithelium for pancytokeratin and uroplakin Ⅱ and TE-7 confirmed pure populations. After in vitro proliferation, cells were seeded onto a surface-modified urethral scaffold with non-knitted filaments. The morphology and viability of the cells were examined by immunohistochemical and fluorescence staining.Inverted and scanning microscopes were used to document cell growth and adhesion.Results Three to five days after primary culture, the uroepithelial cells gradually became confluent, assuming a cobblestone pattern. The filaments of the urethral scaffold had excellent biocompatibility and allowed growth of the uroepithelium, without affecting viability. The uroepithelial cells adhered to and grew well on the scaffold. After 3-7 days,the cells grew vigorously and meshes of the scaffold were full of uroepitheliums.Conclusions The surface-modified urethral scaffold with non-knitted filaments allows the growth of uroepithelium and can serve as a carrier for the tissue engineering of urethra.

High-entropy alloy stabilized and activated Pt clusters for highly efficient electrocatalysis

Although Pt and other noble metals are the state-of-the-art catalysts for various energy conversion applications,their low reserve,high cost,and instability limit their large-scale utilization.Herein,we report a hybrid catalysts design featuring noble metal clusters(e.g.,Pt)uniformly dispersed and stabilized on high-entropy alloy nanoparticles(HEA,e.g.,FeCoNiCu),denoted as HEA@Pt,which is prepared via ultra-fast shock synthesis(∼300 ms)for HEA alloying combined with Pt galvanic replacement for surface anchoring.In our design,the HEA core critically ensures high dispersity,stability,and tunability of the surface Pt clusters through high entropy stabilization and core-shell interactions.As an example in the hydrogen evolution reaction,HEA@Pt achieved a significant mass activity of 235 A/gPt,which is 9.4,3.6,and 1.9-times higher compared to that of homogeneous FeCoNiCuPt(HEA-Pt),Pt,and commercial Pt/C,respectively.We also demonstrated noble Ir stabilized on FeCoNiCrMn nanoparticles(HEA-5@Ir),achieving excellent anodic oxygen evolution performance and highly efficient overall water splitting when combined with the cathodic HEA@Pt.Therefore,our work developed a general catalysts design strategies by using high entropy nanoparticles for effective dispersion,stabilization,and modulation of surface active sites,achieving a harmonious combination of high activity,stability,and low cost.