Enhanced charge separation by incomplete calcination modified co-doped TiO_(2)nanoparticle for isothiazolinone photocatalytic degradation

Photocatalytic oxidation techniques are promising for degradation of the highly ecotoxic and refractory isothiazolinone bactericides in relevant industrial wastewaters.However,low charge separation and directional transport efficiency under solar light radiation restrain their practical application.Here,we report a nanostructured photocatalyst doped with Gd and B in TiO_(2)with carbon incorporation and defect formation through incomplete calcination.The specific surface area,grain size,and hydrophilicity of TiO_(2)are improved,which is beneficial for the interfacial reaction between the photocatalyst and pollutants.The reduction of the bandgap,the broadening of the photo-absorption range,and the retarded electron-hole recombination promote the photocatalytic performance due to the improved oxygen vacancies based on the electron distribution modification.The difference in partial density of states(ΔPDOS)between the current catalyst and raw TiO_(2)indicates that the co-doping of Gd and B with incomplete calcination changes the electronic hybridization of conduction band and valence band near the Fermi level,and affects the band gap energy.It improved charge separation and directional transport efficiency and benefited the formation of main active species,including•OH and O_(2)•−,for the pollutant decomposition.The rate of photocatalytic removal of benzisothiazolinone(BIT)by the current photocatalyst reaches 1.25 h^(−1),being 4.31 times that of TiO_(2).The current work offers a constructive approach to the design and synthesis of nanostructured photocatalysts for the photocatalytic degradation of refractory organic pollutants.

ZIF-Mediated Anchoring of Co species on N-doped Carbon Nanorods as an Efficient Cathode Catalyst for Zn-Air Batteries

Developing efficient oxygen reduction reaction(ORR)catalyst is essential for the practical application of Zn-air batteries(ZABs).In this contribution,we develop a novel zeolitic imidazolate framework(ZIF)-mediated strategy to anchor Co species on N-doped carbon nanorods for efficient ORR.Featuring ultrahigh N-doping(10.29 at.%),monodisperse Co nanocrystal decoration,and well-dispersed Co-N_(x)functionalization,the obtained Co-decorated N-doped carbon nanorods(Co@NCNR)exhibit a decent ORR performance comparable to commercial Pt/C in alkaline media.Aqueous ZABs have been assembled using Co@NCNR as the cathode catalyst.The assembled ZABs manifest high initial open-circuit voltage as well as high energy density.In addition,the Co@NCNR also demonstrates ideal ORR performance in quasi-solid-state ZABs.

Intelligent model prediction of fluctuant increase of maximum electric field in XLPE insulation using long short-term memory network algorithm

The electric field distortion due to space charge accumulations plays a significant role in the ageing,degradation and breakdown in failure of HVDC power cables.Currently,limited experimental results of the electric field dominated by space charges are insufficient to diagnose the power cables.This paper proposes an improved long short-term memory network(LSTM)model for predicting the fluctuating maximum electric field(Emax)in cross-linked polyethylene(XLPE)cable insulation.The various Emax data derived from the complex space charge behaviours were measured using the pulsed electroacoustic method.The model uses regularisation and dropout feedback in the LSTM unit,reducing the phenomenon of over-fitting due to the limited data.It enhances the prediction accuracy and ability of long time prediction by improving the prediction of Emax with the non-linear fluctuation.The predicted Emax approaches 190 kV/mm under 150 kV/mm and 60°C after 2 h.The predicted large variation in Emax under 120 kV/mm and 20°C after 4 h ranges from 130 to 160 kV/mm.It indicates high electric stress in the cable insulation during continuous operation.The proposed LSTM model is of great importance to guide the diagnosis of cable degradation in HVDC power cables.

A standardized method to create peripheral nerve injury in dogs using an automatic non-serrated forceps

This study describes a method that not only generates an automatic and standardized crush injury in the skull base, but also provides investigators with the option to choose from a range of varying pressure revels. We designed an automatic, non-serrated forceps that exerts a varying force of 0 to 100 g and lasts for a defined period of 0 to 60 seconds. This device was then used to generate a crush injury to the right oculomotor nerve of dogs with a force of 10 g for 15 seconds, resulting in a deficit in the pupil-light reflex and ptosis. Further testing of our model with Toluidine-blue staining demonstrated that, at 2 weeks post-surgery disordered oculomotor nerve fibers, axonal loss, and a thinner than normal myelin sheath were visible. Electrophysiological examination showed occasional spontaneous potentials. Together, these data verified that the model for oculomotor nerve injury was successful, and that the forceps we designed can be used to establish standard mechanical injury models of peripheral nerves.

Regenerating nerve fiber innervation of extraocular muscles and motor functional changes following oculomotor nerve injuries at different sites

In the present study, the oculomotor nerves were sectioned at the proximal （subtentorial） and distal （superior orbital fissure） ends and repaired. After 24 weeks, vestibulo-ocular reflex evaluation confirmed that the regenerating nerve fibers following oculomotor nerve injury in the superior orbital fissure had a high level of specificity for innervating extraocular muscles. The level of functional recovery of extraocular muscles in rats in the superior orbital fissure injury group was remarkably superior over that in rats undergoing oculomotor nerve injuries at the proximal end （subtentorium）. Horseradish peroxidase retrograde tracing through the right superior rectus muscle showed that the distribution of neurons in the nucleus of the oculomotor nerve was directly associated with the injury site, and that crude fibers were badly damaged. The closer the site of injury of the oculomotor nerve was to the extraocular muscle, the better the recovery of neurological function was. The mechanism may be associated with the aberrant number of regenerated nerve fibers passing through the injury site.

Expression of Tyrosine-kinase Receptors and Neurotrophins in Human Neuroblastomas

OBJECTIVE The aim of this study was to investigate mRNA expression of tyrosine-kinase receptors （TRKs） and neurotrophins （NTs） in human neuroblastomas. METHODS Expression of TrkA, TrkB, TrkC and BDNF was quantitatively examined by reverse transcription-polymerase chain reaction （RT-PCR） in 27 cases of neuroblastomas. RESULTS The high and total rates of TrkA were expressed in significantly more tumors in a lower-stage group compared to a higher-stage group （P〈0.05） and the high level of TrkA expression was correlated positively with the 2-year cumulative-survival rate of the patients （P〈 0.01）. The high and total rates of TrkB were expressed in significantly more tumors in a higher-stage group compared to a lower-stage group （P〈0.05）. All 3 rates of BDNF expression between the 2 groups showed no statistical difference （P〉0.05）, but the co-expression ratio of TrkB and BDNF showed a remarkable significance in the higher-stage group more than in the lower-stage group （P〈0.05）. TrkC expression was usually accompanied by TrkA expression, but there was only a non-significant trend between TrkC expression and TrkA expression. CONCLUSION RT-PCR for mRNA expression of TRKs and NTs has important clinical significance relating to the tumor stage and outcome for patients with neuroblastomas.

Electronic structure engineering of single atomic sites by plasmoninduced hot electrons for highly efficient and selective photocatalysis

Single atom(SA)catalysts have achieved great success on highly selective heterogeneous catalysis due to their abundant and homogeneous active sites.The electronic structures of these active sites,restrained by their localized coordination environments,significantly determine their catalytic performances,which are difficult to manipulate.Here,we investigated the effect of localized surface plasmon resonance(LSPR)on engineering the electronic structures of single atomic sites.Typically,core–shell structures consisted of Au core and transition metal SAs loaded N-doped carbon(CN)shell were constructed,namely Au@M-SA/CN(M=Ni,Fe,and Co).It was demonstrated that plasmon-induced hot electrons originated from Au were directionally injected to the M-SAs under visible light irradiation,which significantly changed their electronic structures and meanwhile facilitated improved overall charge separation efficiency.The as-prepared Au@Ni-SA/CN exhibited highly efficient and selective photocatalytic CO_(2) reduction to CO performance,which is 20.8,17.5,and 6.9 times those of Au nanoparticles,Au@CN,and Ni-SA/CN,respectively.Complementary spectroscopy analysis and theoretical calculations confirmed that the plasmon enhanced Ni-SA/CN sites featured increased charge density for efficient intermediate activation,contributing to the superb photocatalytic performance.The work provides a new insight on plasmon and atomic site engineering for efficient and selective catalysis.

Inhaled multilevel size-tunable,charge-reversible and mucus-traversing composite microspheres as trojan horse:Enhancing lung deposition and tumor penetration

Dry powder inhalation represents a promising approach for the treatment of lung cancer,offering several advantages such as enhanced targeting,improved bioavailability,and reduced toxicity.However,traditional dry powder formulations suffer from limitations,notably low pulmonary delivery efficiency and inadequate penetration into tumor tissues,thereby limiting their therapeutic efficacy.In response to these challenges,we have developed an innovative trojan horse strategy,harnessing an inhalable nanoparticlein-microsphere system characterized by tunable size,reversible charge,and mucus-penetrating capabilities.The inhalable nanoparticle-in-microsphere system exhibit stable structural properties,excellent environmental responsiveness and high biocompatibility.More importantly,the therapeutic effect of MTX@PAMAM@HA@Gel(MPHG)was demonstrated in vitro and in vivo.This system offers improved pulmonary delivery efficiency,enhanced drug retention within tumor tissues,and effective penetration,thus representing a promising strategy in lung cancer treatment.

Flexible head-following motion planning for scalable and bendable continuum robots

Continuum robots,which are characterized by high length-to-diameter ratios and flexible structures,show great potential for various applications in confined and irregular environments.Due to the combination of motion modes,the existence of multiple solutions,and the presence of complex obstacle constraints,motion planning for these robots is highly challenging.To tackle the challenges of online and flexible operation for continuum robots,we propose a flexible head-following motion planning method that is suitable for scalable and bendable continuum robots.Firstly,we establish a piecewise constant curvature(PCC)kinematic model for scalable and bendable continuum robots.The article proposes an adaptive auxiliary points model and a method for updating key nodes in head-following motion to enhance the precise tracking capability for paths with different curvatures.Additionally,the article integrates the strategy for adjusting the posture of local joints of the robot into the head-following motion planning method,which is beneficial for achieving safe obstacle avoidance in local areas.The article concludes by presenting the results of multiple sets of motion simulation experiments and prototype experiments.The study demonstrates that the algorithm presented in this paper effectively navigates and adjusts posture to avoid obstacles,meeting the real-time demands of online operations.The average time for a single-step solution is 4.41×10^(-5) s,and the average tracking accuracy forcircular paths is 7.8928mm.

Multi-harmonic equivalent modeling for a planar repetitive structure with polynomial-nonlinear joints

How nonlinear joints affect the response of large space structures is an important problem to investigate.In this paper,a multi-harmonic equivalent modeling method is presented to establish a frequency-domain model of planar repetitive structures with nonlinear joints.First,at the local level,the nonlinear joint is modeled by the multi-harmonic describing function matrix.The element of the hybrid beam is obtained by the dynamic condensation of the beam-joint element.Second,at the global level,the displacement-equivalence method is used to model the multi-harmonic Euler continuum beam equivalent to the planar repetitive structure.Then,the pseudo-arc-length continuation method is applied to track the multi-harmonic trajectory of response.Afterwards,an experiment is conducted to validate the correctness of the modeling method,considering the effect of hanging rope and air damping.In the numerical studies,several simulation results indicate the similarity of response between a single-degree-of-freedom system with a single nonlinear joint and the system of the planar repetitive structure with a large number of nonlinear joints.Finally,the component of higher-order harmonics is shown to be important for predicting the resonance frequencies and amplitudes.

Colloidal Synthesis of Semiconductor Films for Efficient Photoelectrochemical Hydrogen Generation

The semiconductor-based photoanodes have shown great potential on photoelectrochemical(PEC)hydrogen generation.Compared to the pristine semiconductor,photoanodes fabricated with doped semiconductors exhibit modulated bandgap structure and enhanced charge separation efficiency,demonstrating improved optoelectronic properties.In this work,we develop a colloidal cation exchange(CE)strategy on versatile synthesis of heterovalent doped chalcogenide semiconductor thin films with high surface roughness.Using Ag-doped CdSe(CdSe:Ag)thin films as an example,the organized centimeter-scale CdSe:Ag films with nanometer-scale thickness(thickness around 80 nm,length×width around 1.5 cm×1.2 cm)exhibit enhanced optical absorbance ability and charge carrier density by tuning the energy levels of conduction and valence bands as well as improved electrical conductivity by Ag dopants compared to the pristine CdSe film obtained by the vapor-phase vacuum deposition strategy.In the meantime,the surface roughness of the as-prepared semiconductor thin films is also increased with abundantly exposed active sites to facilitate accessibility to water for hydrogen generation and suppress photogenerated carrier recombination.The CdSe:Ag film photoanodes exhibit superb PEC hydrogen generation performance with a photocurrent density of 0.56 mA/cm^(2) at 1.23 V versus reversible hydrogen electrode,which is nearly 3 times higher than the pristine CdSe film.This work provides a new strategy on colloidal synthesis of photoelectrodes with modulated heterovalent doping and surface roughness for PEC applications.

具有区间参数的陀螺柔性结构动响应分析

本文研究了带有不确定性参数的陀螺柔性结构动态响应.首先假设柔性结构含有不确定性参数且有界,建立一个受扰动的陀螺柔性结构模型.随后,提出一种有理级数展开-区间摄动有限元方法(RSE-IPFEM),用于估计陀螺柔性结构的区间动响应上下界.最后,给出了两个数值算例结果,并与摄动有限元法(IPFEM)、蒙特卡罗方法(MCM)计算的结果相对比,证明了RSE-IPFEM方法的有效性和可行性.结果表明,弹性模量和陀螺转子速度的不确定性对陀螺柔性结构的动响应有很大影响.

Modulating the local coordination environment of single-atom catalysts for enhanced catalytic performance

The local coordination environment of catalysts has been investigated ftor an extended period to obtain enhanced catalytic performance.Especially with the advancement of single-atom catalysts(SACs),research on the coordination environment has been advanced to the atomic level.The surrounding coordination atoms of central metal atoms play important roles in their catalytic activity,selectivity and stability.In recent years,remarkable improvements of the catalytic performance of SACs have been achieved by the tailoring of coordination atoms,coordination numbers and second-or higher-coordination shells,which provided new opportunities for the further development of SACs.In this review,the characterization of coordination environment,tailoring of the local coordination environment,and their related adjustable catalytic performance will be discussed.We hope this review will provide new insights on further research of SACs.

From core-shell to yolk-shell:Keeping the intimately contacted interface for plasmonic metal@semiconductor nanorods toward enhanced near-infrared photoelectrochemical performance

Here we report a synthetic strategy for controllable construction of yolk-shell and core-shell plasmonic metal@semiconductor hybrid nanocrystals through modulating the kinetics of sulfurization reaction followed by cation exchange.The yielded yolk-shell structured products feature exceptional crystallinity and more importantly,the intimately adjoined and sharp interface between plasmonic metal and semiconductor which facilitates efficient charge carrier communications between them.By exploiting the system composed of Au nanorods and p-type PbS as a demonstration,we show that the Au@PbS yolk-shell nanorods manifest notable improvement in visible and near infrared light absorption compared to the Au@PbS core-shell nanorods as well as hollow PbS nanorods.Moreover,the photocathode constituted by Au@PbS yolk-shell nanorods affords the highest photoelectrochemical activities both under simulated sunlight andλ>700 nm light irradiation.The superior performance of Au@PbS yolk-shell nanorods is considered arising from the combination of the favorable structural advantages of yolk-shell configuration and the surface plasmon resonance enhancement effect.We envision that the reported synthetic strategy can offer a valuable means to create hybrid nanocrystals with desirable structures and functions that enable to harness the photogenerated charge carriers,including the plasmonic hot holes,in wide-range solar-to-fuel conversion.

Interfacial engineering of 3D hollow CoSe_(2)@ultrathin MoSe_(2)core@shell heterostructure for efficient pH-universal hydrogen evolution reaction

Rational design and construction of low-cost and highly efficient electrocatalysts for hydrogen evolution reaction(HER)is meaningful but challenging.Herein,a robust three dimensional(3D)hollow CoSe_(2)@ultrathin MoSe_(2)core@shell heterostructure(CoSe_(2)@MoSe_(2))is proposed as an efficient HER electrocatalyst through interfacial engineering.Benefitting from the abundant heterogeneous interfaces on CoSe_(2)@MoSe_(2),the exposed edge active sites are maximized and the charge transfer at the hetero-interfaces is accelerated,thus facilitating the HER kinetics.It exhibits remarkable performance in pH-universal conditions.Notably,it only needs an overpotential(η10)of 108 mV to reach a current density of 10 mA·cm^(-2)in 1.0 M KOH,outperforming most of the reported transition metal selenides electrocatalysts.Density functional theory(DFT)calculations unveil that the heterointerfaces synergistically optimize the Gibbs free energies of H2O and H^(*)during alkaline HER,accelerating the reaction kinetics.The present work may provide new construction guidance for rational design of high-efficient electrocatalysts.

Microreactor platform for continuous synthesis of electronic doped quantum dots

Electronic doped quantum dots(Ed-QDs),by heterovalent cations doping,have held promise for future device concepts in optoelectronic and spin-based technologies due to their broadband Stokes-shifted luminescence,enhanced electrical transport and tailored magnetic behavior.Considering their scale-up requirement and the low yielding of several current colloidal synthesis methods,a stable and efficient bulk synthesis strategy must be developed.Microreactors have long been recognized as an effective platform for producing nanomaterials and fabricating large-scale structures.Here,we chose microreactor platform for continuous synthesis of Ed-QDs in the air at low temperatures.By original reverse cation exchange reaction mechanism together with varying the kinetic conditions of microreactor platform,such as liquid flow rate,the Ag doped CdS(CdS:Ag)Ed-QDs with higher yield have been synthesized successfully due to the continuous synthesis advantages with a high degree of size selectivity.Enabled by microreactor engineering simulation,this research not only provides a new synthetic method towards scale-up production but also enables to improve chemical mass production of similar functional QDs for optical devices,bioimaging and innovative information processing applications.