Biocatalytic enhancement of laccase immobilized on ZnFe_(2)O_(4) nanoparticles and its application for degradation of textile dyes

Efficient and convenient treatment of industrial dyeing wastewater is of great significance to guarantee human and animal health.This work presented the enhanced catalytic activity at pH 3.0 of laccase immobilized on amino-functionalized ZnFe_(2)O_(4) nanoparticles(ZnFe_(2)O_(4)-laccase)and its application for the degradation of textile dyes.Due to the existence of a large number of oxygen vacancies on the surface of the ZnFe_(2)O_(4) nanoparticles,negative ions accumulated on the magnetic carriers,which resulted in a harsh optimal pH value of the ZnFe_(2)O_(4)-laccase.Laccase activity assays revealed that the ZnFe_(2)O_(4)-laccase possessed superior pH and thermal stabilities,excellent reusability,and noticeable organic solvent tolerance.Meanwhile,the ZnFe_(2)O_(4) laccase presented efficient and sustainable degradation of high concentrations of textile dyes.The initial decoloration efficiencies of malachite green(MG),brilliant green(BG),azophloxine,crystal violet(CV),reactive blue 19(RB19),and procion red MX-5B were approximately 99.1%,95.0%,93.3%,87.4%,86.1%,and 85.3%,respectively.After 10 consecutive reuses,the degradation rates of the textile dyes still maintained about 98.2%,92.5%,83.2%,81.5%,79.8%and 65.9%,respectively.The excellent dye degradation properties indicate that the ZnFe_(2)O_(4)-laccase has a technical application in high concentrations of dyestuff treatment.

局部T晚期与N晚期鼻咽癌患者的预后比较

目的:回顾性分析局部T晚期与N晚期鼻咽癌患者的预后情况,为临床鼻咽癌治疗提供参考.方法:选取2011年12月至2017年11月西部战区总医院经病理确诊为鼻咽癌的局部T晚期患者102例、局部N晚期患者162例的临床病例资料,分为两组并分析患者的预后情况.结果:局部T晚期与N晚期患者5年总生存率(overall survival,OS)分别为82.8%与75.8%(P=0.271)、无疾病进展生存率(progression-free survival,PFS)分别为73.7%与62.8%(P=0.043),无局部复发生存率(local relapse-free survival,LRFS)分别为87.6%与91.6%(P=0.646)、无远处转移生存率(distant metastasis-free survival,DMFS)分别为87.7%与79.5%(P=0.066),两组间PFS差异具有统计学意义.结论:局部N晚期鼻咽癌患者的DMFS、OS、PFS均有下降趋势,临床上局部N晚期鼻咽癌患者应更强调系统性治疗以及分层治疗的意义,以争取更高的OS并降低远处转移.

Molybdosphoric Acid Mixed with Titania Used as a Catalyst to Synthesize Diphenyl Carbonate via Transesterification of Dimethyl Carbonate and Phenol

The 12-molybdosphoric acid mixed with titania （MPA-TiO2） was found to be a novel and efficient catalyst for the synthesis of diphenyl carbonate （DPC） via transesterification of dimethyl carbonate （DMC） and phenol. The X-ray diffraction （XRD） and infrared （IR） techniques were employed to characterize the prepared catalysts. The effect of the weight ratio of the 12-molybdosphoric acid to titania on the transesterification was investigated. A 13.1% yield of DPC and an 11.6% yield of methyl phenyl carbonate （MPC） were obtained over MPA-TiO2 with the weight ratio of MPA to TiO2 as 5：1.

Review：A Survey of Single Gimbal Control Moment Gyroscope forAgile Spacecraft Attitude Control

Agile attitude maneuver is a basic requirement for next generation imaging spacecraft and Control Moment Gyroscope (CMG) is an effective candidate for large space station and agile spacecraft attitude control because of its torque amplification capability. This paper provides a thorough survey of Single Gimbal Control Moment Gyroscope (SGCMG) in terms of configuration,evaluation,modeling,singularity analysis and steering logic,etc. For specific space missions,CMGs are logically mounted into different particular arrays which can be chosen by the proposed evaluation methods. From the dynamic model we find a tough inverse mapping problem which suffers the inherent geometric singularity. Different techniques and theories then are applied for singularity analysis and CMG steering logics design. The pyramid CMG cluster and singular robust logics are proven to be able to enhance the agility of spacecraft. Above work forms a systematic framework of SGCMG for agile spacecraft control with lots of illustrative examples,tables and figures,and will evoke further investigation for future missions.

Transcriptomic,proteomic,and phosphoproteomic analyses reveal dynamic signaling networks influencing long-grain rice development

The LGS1(Large grain size 1)gene,also known as GS2/GL2/Os GRF4,is involved in regulating grain size and quality in rice,but the mechanism governing grain size has not been elucidated.We performed transcriptomic,proteomic,and phosphoproteomic analyses of young rice panicles in Samba(a wild-type cultivar with extra-small grain)and NIL-LGS1(a nearly isogenic line of LGS1 with large grain in the Samba genetic background)at three developmental stages(4–6)to identify internal dynamic functional networks determining grain size that are mediated by LGS1.Differentially expressed proteins formed seven highly functionally correlated clusters.The concordant regulation of multiple functional clusters may be key features of the development of grain length in rice.In stage 5,16 and 24 phosphorylated proteins were significantly up-regulated and down-regulated,and dynamic phosphorylation events may play accessory roles in determining rice grain size by participating in protein–protein interaction networks.Transcriptomic analysis in stage 5 showed that differentially expressed alternative splicing events and dynamic gene regulatory networks based on 39 transcription factors and their highly correlated target genes might contribute to rice grain development.Integrative multilevel omics analysis suggested that the regulatory network at the transcriptional and posttranscriptional levels could be directly manifested at the translational level,and this analysis also suggested a regulatory mechanism,regulation of protein translation levels,in the biological process that extends from transcript to protein to the development of grain.Functional analysis suggested that biological processes including MAPK signaling,calcium signaling,cell proliferation,cell wall,energy metabolism,hormone pathway,and ubiquitin-proteasome pathway might be involved in LGS1-mediated regulation of grain length.Thus,LGS1-mediated regulation of grain size is affected by dynamic transcriptional,posttranscriptional,translational and posttranslational changes.

Multi-Feature Fusion Based Relative Pose Adaptive Estimation for On-Orbit Servicing of Non-Cooperative Spacecraft

On-orbit servicing, such as spacecraft maintenance, on-orbit assembly, refueling, and de-orbiting, can reduce the cost of space missions, improve the performance of spacecraft, and extend its life span. The relative state between the servicing and target spacecraft is vital for on-orbit servicing missions, especially the final approaching stage. The major challenge of this stage is that the observed features of the target are incomplete or are constantly changing due to the short distance and limited Field of View (FOV) of camera. Different from cooperative spacecraft, non-cooperative target does not have artificial feature markers. Therefore, contour features, including triangle supports of solar array, docking ring, and corner points of the spacecraft body, are used as the measuring features. To overcome the drawback of FOV limitation and imaging ambiguity of the camera, a "selfie stick" structure and a self-calibration strategy were implemented, ensuring that part of the contour features could be observed precisely when the two spacecraft approached each other. The observed features were constantly changing as the relative distance shortened. It was difficult to build a unified measurement model for different types of features, including points, line segments, and circle. Therefore, dual quaternion was implemented to model the relative dynamics and measuring features. With the consideration of state uncertainty of the target, a fuzzy adaptive strong tracking filter( FASTF) combining fuzzy logic adaptive controller (FLAC) with strong tracking filter(STF) was designed to robustly estimate the relative states between the servicing spacecraft and the target. Finally, the effectiveness of the strategy was verified by mathematical simulation. The achievement of this research provides a theoretical and technical foundation for future on-orbit servicing missions.

Kinetics Research on In-situ Rapid Dechlorination of 1,4-dichlorobenzene by Microwave-assisted Raney Ni-Al Alloy Catalyst

[Objective]The research aimed to study rapid dechlodnation kinetics of 1,4-dichlorobenzene （1,4-DCB） by microwave-assisted Raney Ni -AI alloy catalyst. [ Method] Microwave-assisted Raney Ni -AI alloy catalyst was used for dechlorination of chlorobenzene （CB） and 1,4-DCB to analyze dechlorination kinetics of 1,4-DCB. [ Result] Reductive dechlorination reaction of 1,4-DCB by microwave-assisted Raney Ni- AI alloy catalyst was in accordance of the two-order reaction kinetics. Reaction rate constants of 1,4-DCB dechlorination at 35 and 50 ℃ were 0.037 6 and 0.151 mol/（ L . min）, and the activation energy was 76.66 kJ/mol. By microwave-assisted Raney Ni - AI alloy catalyst, dechlorination rate of 1,4- DCB reached 90% at 10 rain and 35 ℃. Moreover, two chlorine atoms were removed simultaneously, reaching the target of efficient dechlorination. [ Condusion] Oechlodnation of polychlodnated organic compounds by microwave-assisted Raney Ni- AI alloy catalyst obtained good effect .

任意区域的网格自动生成和任意高阶有限元方法

本文首先简要介绍非拟合网格有限元方法求解复杂区域上椭圆问题的发展现状.然后结合最近本文作者发展的非拟合网格有限元方法,针对二阶椭圆方程提出一种任意光滑区域上的任意高阶协调有限元方法.本文在带悬点的Cartesian网格上自动生成诱导网格,在诱导网格上构造协调的高阶有限元空间,采用Nitsche技术处理Dirichlet边界条件,并证明方法的适定性和hp先验误差估计.数值算例验证了本文的理论结果.

Naked-eye visualization of lymph nodes using fluorescence nanoprobes in non-human primate-animal models

Despite sufficient studies performed in non-primate animal models,there exists scanty information obtained from pilot trials in non-human primate animal models,severely hindering nanomaterials moving from basic research into clinical practice.We herein present a pioneering demonstration of nanomaterials based optical imaging-guided surgical operation by using macaques as a typical kind of non-human primate-animal models.Typically,taking advantages of strong and stable fluorescence of the small-sized(diameter:~5 nm)silicon-based nanoparticles(SiNPs),lymphatic drainage patterns can be vividly visualized in a real-time manner,and lymph nodes(LN)are able to be sensitively detected and precisely excised from small animal models(e.g.,rats and rabbits)to non-human primate animal models(e.g.,cynomolgus macaque(Macaca fascicularis)and rhesus macaque(Macaca mulatta)).Compared to clinically used invisible near-infrared(NIR)lymphatic tracers(i.e.,indocyanine green(ICG);etc.),we fully indicate that the SiNPs feature unique advantages for naked-eye visible fluorescence-guided surgical operation in long-term manners.Thorough toxicological analysis in macaque models further provides confirming evidence of favorable biocompatibility of the SiNPs probes.We expect that our findings would facilitate the translation of nanomaterials from the laboratory to the clinic,especially in the field of cancer treatment.

An ultra-deep TSV technique enabled by the dual catalysis-based electroless plating of combined barrier and seed layers

Silicon interposers embedded with ultra-deep through-silicon vias(TSVs)are in great demand for the heterogeneous integration and packaging of opto-electronic chiplets and microelectromechanical systems(MEMS)devices.Considering the cost-effective and reliable manufacturing of ultra-deep TSVs,the formation of continuous barrier and seed layers remains a crucial challenge to solve.Herein,we present a novel dual catalysis-based electroless plating(ELP)technique by tailoring polyimide(PI)liner surfaces to fabricate dense combined Ni barrier/seed layers in ultradeep TSVs.In additional to the conventional acid catalysis procedure,a prior catalytic step in an alkaline environment is proposed to hydrolyze the PI surface into a polyamide acid(PAA)interfacial layer,resulting in additional catalysts and the formation of a dense Ni layer that can function as both a barrier layer and a seed layer,particularly at the bottom of the deep TSV.TSVs with depths larger than 500μm and no voids are successfully fabricated in this study.The fabrication process involves low costs and temperatures.For a fabricated 530-μm-deep TSV with a diameter of 70μm,the measured depletion capacitance and leakage current are approximately 1.3 pF and 1.7 pA at 20 V,respectively,indicating good electrical properties.The proposed fabrication strategy can provide a cost-effective and feasible solution to the challenge of manufacturing ultra-deep TSVs for modern 3D heterogeneous integration and packaging applications.

Nanoscale electric field sensing using a levitated nano-resonator with net charge

The nanomechanical resonator based on a levitated particle exhibits unique advantages in the development of ultrasensitive electric field detectors. We demonstrate a three-dimensional, high-sensitivity electric field measurement technology using the optically levitated nanoparticle with known net charge. By scanning the relative position between nanoparticle and parallel electrodes, the three-dimensional electric field distribution with microscale resolution is obtained. The measured noise equivalent electric intensity with charges of 100e reaches the order of 1 μV·cm^(-1)·Hz^(-1/2)at 1.4 × 10^(-7) mbar. Linearity analysis near resonance frequency shows a measured linear range over 91 d B limited only by the maximum output voltage of the driving equipment. This work may provide an avenue for developing a high-sensitivity electric field sensor based on an optically levitated nano-resonator.

Yoctonewton force detection based on optically levitated oscillator

Optically levitated oscillators in high vacuum have excellent environmental isolation and low mass compared with conventional solid-state sensors,which makes them suitable for ultrasensitive force detection.The force resolution usually scales with the measurement bandwidth,which represents the ultimate detection capability of the system under ideal conditions if sufficient time is provided for measurement.However,considering the stability of a real system,a method based on the Allan variance is more reliable to evaluate the actual force detection performance.In this study,a levitated optomechanical system with a force detection sensitivity of 6.33±1.62 zN/Hz^(1/2)was demonstrated.And for the first time,the Allan variance was introduced to evaluate the system stability due to the force sensitivity fluctuations.The force detection resolution of 166.40±55.48 yN was reached at the optimal measurement time of 2751 s.The system demonstrated in this work has the best force detection performance in both sensitivity and resolution that have been reported so far for optically levitated particles.The reported high-sensitivity force detection system is an excellent candidate for the exploration of new physics such as fifth force searching,high-frequency gravitational waves detection,dark matter research and so on.

Integrating surface and interface engineering to improve optoelectronic performance and environmental stability of MXenebased heterojunction towards broadband photodetection

Two-/three-dimensional(2D/3D)heterojunction-based photodetectors have attracted much attention due to their highly efficient photoelectric conversion driven by the built-in electric field for high-speed photoresponse.However,a large dark current induced by unexpected surface states at the interface between 2D materials and 3D bulks is widely observed in such structures,greatly degrading their optoelectronic performance.Herein,a heterojunction of proton acid HCl treated MXene(H-MXene)/TiO_(2)/Si via integrating surface and interface engineering is fabricated,which exhibits decreased dark current and improved environmental stability.A feasible strategy to optimize the interface properties between MXene and Si is proposed by an in-situ oxidation process of MXene into TiO_(2),resulting in a suppressed dark current as well as high specific detectivity.Benefitting from the enhanced light absorption of MXene on the bulk Si substrate,the photoresponse of as-fabricated devices in the near-infrared region is also elevated.Moreover,the treatment of proton acid HCl on the surface of MXene brings better conductivity and environmental stability due to the decreased layer spacing of MXene,which is further confirmed by both experimental and theoretical methods.This work opens a unique way to comprehensively boost the optoelectronic performance of MXene-based photodetectors.

Cu_(1)-B dual-active sites catalysts for the efficient dehydrogenative coupling and CO_(2)electroreduction

Dual-active sites(DASs)catalysts have positive potential applications in broad fields because of their specific active sites and synergistic catalytic effects.Therefore,the controllable synthesis and finely regulating the activity of such catalysts has become a hot research area for now.In this work,we developed a pyrolysis-etching-hydrogen activation strategy to prepare the DASs catalysts involving single-atom Cu and B on N-doped porous carbon material(Cu_(1)-B/NPC).Numerous systematic characterization and density functional theoretical(DFT)calculation results showed that the Cu and B existed as Cu-N4 porphyrinlike unit and B-N_(3)unit in the obtained catalyst.DFT calculations further revealed that single-atom Cu and B sites were linked by bridging N atoms to form the Cu_(1)-B-N6 dual-sites.The Cu_(1)-B/NPC catalyst was more effective than the single-active site catalysts with B-N_(3)sites in NPC(B/NPC)and Cu-N4 porphyrin-like sites in NPC(Cu_(1)/NPC),respectively,for the dehydrogenative coupling of dimethylphenylsilane(DiMPSH)with various alcohols,performing the great activity(>99%)and selectivity(>99%).The catalytic performances of the Cu_(1)-B/NPC catalyst remained nearly unchanged after five cycles,also indicating its outstanding recyclability.DFT calculations showed that the Cu_(1)-B-N6 dual-sites exhibited the lowest energy profile on the potential energy surface than that of sole B-N_(3)and Cu-N4 porphyrin-like sites.Furthermore,the rate-limiting step of dehydrogenation of DiMPSH on Cu_(1)-B-N6 dual-sites also showed a much lower activation energy than the other two single sites.Benefitting from the superiority of the Cu_(1)-B-N6 dual-sites,the Cu_(1)-B/NPC catalyst can also be used for CO_(2)electroreduction to produce syngas.Thus,DASs catalysts are promising to achieve multifunctional catalytic properties and have aroused positive attention in the field of catalysis.

Derivation and validation of a similarity law for free-flight wind tunnel tests of parallel stage separation

Aiming at the safety problem of the stage separation of parallel reusable high-speed air vehicles,this paper studies the unsteady test method and focuses on deriving a similarity law of parallel stage separation free-flight wind tunnel tests.The new similarity law considers the influences of aerodynamic force and gravity on the motions of the two stages,as well as the influence of aerodynamic interference between the two stages on each other’s motion.From the perspective of multiangle physical equations,the conditions to ensure that the two-stage separation trajectory of a wind tunnel test is similar to that of a real air vehicle are derived innovatively,so as to ensure the authenticity and credibility of wind tunnel test results.The similarity law is verified by an HIFiRE-5 air vehicle,and the separation trajectories of wind tunnel tests and the real air vehicle are obtained by numerical simulation.The research shows that the similarity law derived in this paper can ensure that wind tunnel free-flight tests have the ability to predict the two-stage separation characteristics of real parallel vehicles.By analyzing the separation trajectory curve of the typical state,it is found that the new method can ensure that the trajectory error of a wind tunnel test does not exceed 1%,which indicates that this method is credible.The establishment of the new method lays the foundation for subsequent wind tunnel tests and provides support for research on the safety of the stage separation of parallel reusable air vehicles.

Anisotropic coherence induced nonuniform amplification in N_(2)^(+)

The continuous progress in N_(2)^(+)lasing recently stimulates a great deal of interest in nonlinear and quantum optics of molecular ions,while a complete description of the ionic polarization is still lacking to date.In this work,we are dedicated to constructing the fundamental ionic polarization theory where several ubiquitous strong-field processes including ionization,electronic couplings and molecular alignment jointly determine the spatial arrangement of ions.With the model,the elusive polarization of N_(2)^(+)lasing can be well interpreted.Our results show that the different electronic transition rules for strong-field ionization and resonant couplings result in peculiar population distributions of various electronic states of N_(2)^(+)in space.Meanwhile,the spatial nonuniformity of population distribution can be aggravated or mitigated during field-free evolutions of coherent molecular rotational wave packets.Furthermore,when a follow-up resonant seed pulse interacts with the prepared ionic system,the anisotropic quantum coherence determining the polarization of subsequent N_(2)^(+)lasing can be established.The qualitative agreement between experiments and simulations confirms the validity of the proposed model.The findings provide critical insights into the polarization and radiation mechanisms of molecular ions constructed via ultrafast laser pulses.

High precision attitude dynamic tracking control of a moving space target

On-orbit spacecraft face many threats,such as collisions with debris or other spacecraft.Therefore,perception of the surrounding space environment is vitally important for on-orbit spacecraft.Spacecraft require a dynamic attitude tracking ability with high precision for such missions.This paper aims to address the above problem using an improved backstepping controller.The tracking mission is divided into two phases:coarse alignment and fine alignment.In the first phase,a traditional saturation controller is utilized to limit the maximum attitude angular velocity according to the actuator’s ability.For the second phase,the proposed backstepping controller with different virtual control inputs is applied to track the moving target.To fulfill the high precision attitude tracking requirements,a hybrid attitude control actuator consisting of a Control Moment Gyro(CMG)and Reaction Wheel(RW)is constructed,which can simultaneously avoid the CMG singularity and RW saturation through the use of an angular momentum optimal management strategy,such as null motion.Finally,five simulation scenarios were carried out to demonstrate the effectiveness of the proposed control strategy and hybrid actuator.

Programmable van-der-Waals heterostructure-enabled optoelectronic synaptic floating-gate transistors with ultra-low energy consumption

Van der Waals(vdW)heterostructures provide a unique opportunity to develop various electronic and optoelectronic devices with specific functions by designing novel device structures,especially for bioinspired neuromorphic optoelectronic devices,which require the integration of nonvolatile memory and excellent optical responses.Here,we demonstrate a programmable optoelectronic synaptic floating-gate transistor based on multilayer graphene/h-BN/MoS2 vdW heterostructures,where both plasticity emulation and modulation were successfully realized in a single device.The dynamic tunneling process of photogenerated carriers through the as-fabricated vdW heterostructures contributed to a large memory ratio(105)between program and erase states.Our device can work as a functional or silent synapse by applying a program/erase voltage spike as a modulatory signal to determine the response to light stimulation,leading to a programmable operation in optoelectronic synaptic transistors.Moreover,an ultra-low energy consumption per light spike event(~2.5 fJ)was obtained in the program state owing to a suppressed noise current by program operation in our floating-gate transistor.This study proposes a feasible strategy to improve the functions of optoelectronic synaptic devices with ultra-low energy consumption based on vdW heterostructures designed for highly efficient artificial neural networks.

Characterization of precipitation in the background of atmospheric pollutants reduction in Guilin: Temporal variation and source apportionment

Rainfall samples were collected from three observation sites in Guilin from 2013 to 2017, and the chemical composition characteristics of precipitation and the contribution made by different ion sources were analyzed when atmospheric pollutants levels were reduced. The results showed that acid gas emissions and atmospheric pollutant concentrations continued to decline during the study period. However, the change in the volume-weighted mean p H at the three sites suggested that acid rain pollution was not alleviated and began to deteriorate after 2015. The continuing downward trend for alkaline neutralizing ions(Ca^(2+), NH_4^+) in precipitation indicated that the reduction in alkaline neutralizing substances in the atmosphere was an important factor that led to the deterioration in acid rain across Guilin. The principal component analysis and spearman correlation analysis indicated five sources of ions in precipitation. Quantitative assessment of these five sources indicated that fossil fuel combustion contributed the most ions concentration in precipitation at the three sites, followed by agriculture, terrestrial(crustal) sources, marine sources, and biomass burning. Long-distance airflow might affect the acidity, the electrical conductivity(EC), and ion concentrations in precipitation across Guilin. The airflow trajectory from the west and southeast directions corresponded to higher acidity and ion concentrations. According to the current air pollution control strategy planned by Guilin, reducing atmospheric coarse particles and NH_3 at the same time may potentially lead to further deteriorations in acid rain contents. Therefore, Guilin needs to develop more reasonable pollution prevention measures that synergistically control atmospheric pollutants and acid rain pollution.