化学实验教学中心数字化平台及教学资源建设与实践——以化学省级实验教学示范中心(黑龙江大学)为例

分析了当前高校实验教学示范中心数字化信息建设方面存在的问题,阐述了教育数字化在化学实验教学改革和教育中的意义,结合本校化学实验中心的实际情况,总结了中心围绕数字化信息平台、数字化教学资源、数字化教学模式三个层面进行的数字化建设与探索。搭建了导向清晰和结构立体的化学实验安全、系统先进和综合创新的虚拟仿真、内容丰富和形式多样的化学基础实验等数字化教学资源,构建了线上线下混合式化学实验安全、理论课+线下实验课+虚拟仿真实验+慕课四维一体实验课程教学模式,取得了一定成效,将为同类高校实验室数字化建设提供参考。

Mixing trait-based corn(Zea mays L.)cultivars increases yield through pollination synchronization and increased cross-fertilization

Abiotic stress such as high temperature at flowering is one of many conditions reducing yield of corn(Zea mays L.).Mixing corn cultivars with diverse functional traits increases within-crop diversity and provides a potential means of mitigating yield losses under stress conditions.We conducted a three-year field study to investigate the effects of cultivar mixtures on kernel setting rate,pollen sources,and yield.This study consisted of six treatments,including two high temperature-tolerant(HTT)monocrops of WK702 and DH701,two high temperature-sensitive(HTS)monocrops of DH605 and DH662,and two HTT–HTS mixtures of WK702-DH605 and DH701-DH662.The anthesis–silking interval(ASI)was 0.9–1.6 days shorter in mixtures than in monocrops.Kernel setting rate was increased in mixtures(86.4%–88.7%)compared with those in monocrops(74.7%–84.1%)as a result of synchrony and complementarity of pollination.Grain yields of the HTT–HTS mixtures increased by 13.3%–18.7%,equivalent to 1169 to1605 kg ha^(-1),in comparison with HTS corn monocrops.The results of SSR markers showed that crossfertilization percentage in corn cultivar mixtures ranged from 29.3%to 47.8%,partially explaining yield improvement.Land equivalent ratio(LER)was 1.12 for corn mixtures and the partial land equivalent ratio(e.g.,>0.5)showed the complementary benefits in corn mixtures.The results indicated that mixing corn cultivars with diverse flowering and drought-tolerance traits increased yields via pollination synchrony.

Optimization of the grain boundary diffusion process by doping gallium and zirconium in Nd–Fe–B sintered magnets

As the channel for grain boundary diffusion(GBD)in Nd–Fe–B magnets,grain boundary(GB)phases have a very important effect on GBD.As doping elements that are commonly used to regulate the GB phases in Nd–Fe–B sintered magnets,the influences of Ga and Zr on GBD were investigated in this work.The results show that the Zr-doped magnet has the highest coercivity increment(7.97 kOe)by GBD,which is almost twice that of the Ga-doped magnet(4.32 kOe)and the magnet without Ga and Zr(3.24 kOe).Microstructure analysis shows that ZrB_(2)formed in the Zr-doped magnet plays a key role in increasing the diffusion depth.A continuous diffusion channel in the magnet can form because of the presence of ZrB_(2).ZrB_(2)can also increase the defect concentration in GB phases,which can facilitate GBD.Although Ga can also improve the diffusion depth,its effect is not very obvious.The micromagnetic simulation based on the experimental results also proves that the distribution of Tb in the Zr-doped magnet after GBD is beneficial to coercivity.This study reveals that the doping elements Ga and Zr in Nd–Fe–B play an important role in GBD,and could provide a new perspective for researchers to improve the effects of GBD.

Transcriptome Analysis of a Wild Eggplant Germplasm M239 in Response to Verticillium dahliae Infection

In this study,wild eggplant germplasm No.M239,which is highly susceptible to Verticillium wilt,was used as the experimental material.The physiological and biochemical indices(SOD,PAL,MDA and soluble protein)of M239 roots were measured at different times(0,12,24,36,48,60 and 72 h)post inoculation with Verticillium dahliae,and the key time points for the M239 response to Verticillium wilt infection were screened.Then,RNA-Seq technology was used to screen the differentially expressed genes(DEGs)in M239 roots at 0,12 and 48 h post-inoculation(hpi).The transcriptional results of M239 were also compared with those resistance genes from some reported wild relative Solanum species(S.sisymbriifolium and S.aculeatissimum).Then some DEGs were chosen for validation by qRT–PCR.The results showed that 12 and 48 hpi were the turning points in the changes in all physiological and biochemical indices.A total of 6,783 DEGs were identified by RNA-Seq,including 6,141 DEGs(3,046 upregulated and 3,095 downregulated)at the M_12 h vs.M_0 h,1,903 DEGs(792 upregulated and 1,111 downregulated)at M_48 h vs.M_12 h,and 1,261 DEGs that appeared simultaneously in both stages.KEGG enrichment analysis showed that there were 5 metabolic pathways enriched from DEGs,which were mostly related to primary metabolism,such as glycolysis,amino acid and ribosome biogenesis.Compared with the NCBI non-redundant protein(NR)database,one Ve2 homologous gene and 8 PR protein-related genes were screened.Transcription factor analysis showed that there were a large number of DEGs,such as MYB,AP2-EREBP,bHLH,NAC and Orphans in the two stages.Compared with the reported Verticillium wilt-resistant wild eggplant species,it was found that there were fewer genes and enriched metabolic pathways in the M239 response to Verticillium wilt infection,and it also lacked the response of some known key resistance genes.These results proved that the above resistance genes and metabolic pathways played a key role in the wild eggplant response to V.dahliae infection.

An Overview of Calibration Technology of Industrial Robots

With the continuous improvement of automation,industrial robots have become an indispensable part of automated production lines.They widely used in a number of industrial production activities,such as spraying,welding,handling,etc.,and have a great role in these sectors.Recently,the robotic technology is developing towards high precision,high intelligence.Robot calibration technology has a great significance to improve the accuracy of robot.However,it has much work to be done in the identification of robot parameters.The parameter identification work of existing serial and parallel robots is introduced.On the one hand,it summarizes the methods for parameter calibration and discusses their advantages and disadvantages.On the other hand,the application of parameter identification is introduced.This overview has a great reference value for robot manufacturers to choose proper identification method,points further research areas for researchers.Finally,this paper analyzes the existing problems in robot calibration,which may be worth researching in the future.

Inverse Eigenvalue Problem for Generalized Arrow-Like Matrices

This paper researches the following inverse eigenvalue problem for arrow-like matrices. Give two characteristic pairs, get a generalized arrow-like matrix, let the two characteristic pairs are the characteristic pairs of this generalized arrow-like matrix. The expression and an algorithm of the solution of the problem is given, and a numerical example is provided.

Research Progress of Osteoporosis Based on the Theory of"Homology of Liver and Kidney"

Osteoporosis is a systemic chronic metabolic bone disease,mainly in the elderly and postmenopausal women.At present,most of the clinical treatment is western medicine,but the curative effect is not very significant.In the treatment of osteoporosis,traditional Chinese medicine(TCM)is mainly based on the overall concept of TCM.This article briefly analyzes osteoporosis from the theory of"liver and kidney homology,"discusses the research on osteoporosis in TCM,and hopes to provide reference for the clinical treatment and research of osteoporosis.

Primary Malignant Giant Cell Tumor of Bone:A Case Report

Primary malignant giant cell tumor of bone is clinically rare,lack of specificity,and often misdiagnosed.Currently,related literature about this tumor remains scarce.One case of primary malignant giant cell tumor of bone was diagnosed and treated in our hospital,and the treatment effect was satisfactory.There was no recurrence or metastasis in 2 years of followup.The report is as follows.

ABAQUS and ANSYS Implementations of the Peridynamics-Based Finite Element Method(PeriFEM)for Brittle Fractures

In this study,we propose the first unified implementation strategy for peridynamics in commercial finite element method(FEM)software packages based on their application programming interface using the peridynamics-based finite element method(PeriFEM).Using ANSYS and ABAQUS as examples,we present the numerical results and implementation details of PeriFEM in commercial FEM software.PeriFEM is a reformulation of the traditional FEM for solving peridynamic equations numerically.It is considered that the non-local features of peridynamics yet possesses the same computational framework as the traditional FEM.Therefore,this implementation benefits from the consistent computational frameworks of both PeriFEM and the traditional FEM.An implicit algorithm is used for both ANSYS and ABAQUS;however,different convergence criteria are adopted owing to their unique features.In ANSYS,APDL enables users to conveniently obtain broken-bond information from UPFs;thus,the convergence criterion is chosen as no new broken bond.In ABAQUS,obtaining broken-bond information is not convenient for users;thus,the default convergence criterion is used in ABAQUS.The codes integrated into ANSYS and ABAQUS are both verified through benchmark examples,and the computational convergence and costs are compared.The results show that,for some specific examples,ABAQUS is more efficient,whereas the convergence criterion adopted in ANSYS is more robust.Finally,3D examples are presented to demonstrate the ability of the proposed approach to deal with complex engineering problems.

Insights into the role of RNA m^(6)A modification in the metabolic process and related diseases

According to the latest consensus,many traditional diseases are considered meta-bolic diseases,such as cancer,type 2 diabetes,obesity,and cardiovascular disease.Currently,metabolic diseases are increasingly prevalent because of the ever-improving living standards and have become the leading threat to human health.Multiple therapy methods have been applied to treat these diseases,which improves the quality of life of many patients,but the overall effect is still unsatisfactory.Therefore,intensive research on the metabolic process and the pathogenesis of metabolic diseases is imperative.N6-methyladenosine(m^(6)A)is an important modification of eukaryotic RNAs.It is a critical regulator of gene expression that is involved in different cellular functions and physiological processes.Many studies have indi-cated that m^(6)A modification regulates the development of many metabolic processes and metabolic diseases.In this review,we summarized recent studies on the role of m^(6)A modifica-tion in different metabolic processes and metabolic diseases.Additionally,we highlighted the potential m^(6)A-targeted therapy for metabolic diseases,expecting to facilitate m^(6)A-targeted strategies in the treatment of metabolic diseases.

Liquid Crystal Based Label-Free Optical Sensors forBiochemical Application

Biochemical sensors have important applications in biology,chemistry,and medicine.Nevertheless,many biochemical sensors are hampered by intricate techniques,cumbersome procedures,and the need for labeling.In the past two decades,it has been discovered that liquid crystals can be used to achieve the optical amplification of biological interactions.By modifying recognition molecules,a variety of label-free biochemical sensors can be created.Consequently,biochemical sensors based on the amplification of liquid crystals have become one of the most promising sensors.This paper describes in detail the optical sensing principle of liquid crystals,sensing devices,and optical detection technologies.Meanwhile,the latest research findings are elucidated.Finally,the challenges and future research directions are discussed.

Monolithic integrated optoelectronic chip for vector force detection

Sensors with a small footprint and real-time detection capabilities are crucial in robotic surgery and smart wearable equipment.Reducing device footprint while maintaining its high performance is a major challenge and a significant limitation to their development.Here,we proposed a monolithic integrated micro-scale sensor,which can be used for vector force detection.This sensor combines an optical source,four photodetectors,and a hemispherical silicone elastomer component on the same sapphire-based AlGaInP wafer.The chip-scale optical coupling is achieved by employing the laser lift-off techniques and the flip-chip bonding to a processed sapphire substrate.This hemispherical structure device can detect normal and shear forces as low as 1mN within a measurement range of 0–220 mN for normal force and 0–15 mN for shear force.After packaging,the sensor is capable of detecting forces over a broader range,with measurement capabilities extending up to 10 N for normal forces and 0.2 N for shear forces.It has an accuracy of detecting a minimum normal force of 25 mN and a minimum shear force of 20 mN.Furthermore,this sensor has been validated to have a compact footprint of approximately 1.5 mm^(2),while maintaining high real-time response.We also demonstrate its promising potential by combining this sensor with fine surface texture perception in the fields of compact medical robot interaction and wearable devices.

KF/La2O2CO3固体碱的制备、表征及催化酯交换反应的性能——一个综合创新实验

固体碱催化剂具有易分离、可循环使用、对设备无腐蚀、可使反应工艺过程连续化等优点。它被认为是催化酯交换反应制备可再生能源生物柴油的一种优异催化剂。本实验是在科研成果的基础上创新设计了一个综合实验。通过浸渍法制备了KF/La2O2CO3固体碱催化剂;利用X射线衍射测定了其物相,使用CO2程序升温脱附技术测定了催化剂的表面碱性;并以三丁酸甘油酯与甲醇进行酯交换反应作为模型反应,考查其催化活性。

环氧大豆油丙烯酸酯浸渍改性速生木材的性能及改性机理

为提高速生木材的综合使用性能,以杉木、樟子松和杨木为研究对象,采用经活性单体稀释的环氧大豆油丙烯酸酯(AESO)对其进行化学浸渍改性,比对不同工艺条件对改性木材综合性能的提升效果。通过傅里叶变换红外光谱对合成的AESO进行结构表征,利用X射线光电子能谱仪(XPS)和扫描电子显微镜(SEM)分析AESO浸渍改性木材的微观机理。结果表明,以苯乙烯(St)为稀释剂,按m(AESO):m(St)=3:1配制的混合体系浸渍速生材并在70℃固化6 h,3种木材的综合性能均获得明显提升。改性杉木的性能提升最为显著,浸渍率为166.1%,固化增重率为157.0%,7 d抗吸水率达到了86.1%,顺纹抗压强度增加了87.2%。XPS分析结果表明,AESO浸渍体系成功渗透到木材内部,渗透方式以横向渗透为主。SEM观察到的微观形貌变化说明,改性后木材的微观结构未遭到破坏,浸渍体系填充、黏附到木材结构组织的细胞壁上并交联固化,细胞壁上的纹孔口被闭塞,极大地提高了速生材的抗吸水性和力学强度。

In Situ Monitoring the Potassium‑Ion Storage Enhancement in Iron Selenide with Ether‑Based Electrolyte

As one of the promising anode materials,iron selenide has received much attention for potassium-ion batteries(KIBs).Nevertheless,volume expansion and sluggish kinetics of iron selenide result in the poor reversibility and stability during potassiation–depotassiation process.In this work,we develop iron selenide composite matching ether-based electrolyte for KIBs,which presents a reversible specific capacity of 356 mAh g^(−1) at 200 mA g^(−1) after 75 cycles.According to the measurement of mechanical properties,it is found that iron selenide composite also exhibits robust and elastic solid electrolyte interphase layer in ether-based electrolyte,contributing to the improvement in reversibility and stability for KIBs.To further investigate the electrochemical enhancement mechanism of ether-based electrolyte in KIBs,we also utilize in situ visualization technique to monitor the potassiation–depotassiation process.For comparison,iron selenide composite matching carbonate-based electrolyte presents vast morphology change during potassiation–depotassiation process.When changing to ether-based electrolyte,a few minor morphology changes can be observed.This phenomenon indicates an occurrence of homogeneous electrochemical reaction in ether-based electrolyte,which results in a stable performance for potassium-ion(K-ion)storage.We believe that our work will provide a new perspective to visually monitor the potassium-ion storage process and guide the improvement in electrode material performance.

Effects of the Fermentation of Lophatherum gracile Brongn on Its Active Ingredients of Total Flavonoids and Total Polysaccharide

[Objectives] In order to explore the effect of fermentation on Lophatherum gracile Brongn. [Methods] The single factor experiment was applied to screen the fermentation conditions of L. gracile Brongn,and the effect of fermentation on the contents of total flavonoids and total polysaccharides was explored. [Results] The experiment defined the best fermentation conditions as: keeping natural state of p H,temperature 35℃,inoculation amount 6%,rotation speed 210 r/min,fermentation time 36 h. The results showed that the content increase of total flavonoids in the fermentation group was 5. 59% higher than the that in the non-fermentation group. [Conclusions]The selected fermentation method could improve the contents of total flavonoids and total polysaccharides.

Nanoporous Metals Based on Metallic Glasses:Synthesis,Structure and Functional Applications

Nanoporous metals have emerged as a new class of functional materials with unique structures and properties.Compared to conventional metals and alloys,nanoporous metals possess a high surface area,unique pore size distribution and enhanced catalytic activity,making them highly desirable for a wide range of applications,such as photonics,sensing,supercapacitors and catalysis.In this review paper,we aim to summarize recent advances in the fabrication,structural regulation and functional applications of nanoporous metals and their composites via the dealloying of metallic glasses.Particularly,we will discuss the factors that affect the nanoporous structure,including precursor composition,dealloying conditions and post-treatment methods.We will also cover topics such as the preparation of immiscible nanoporous metals and the control of hierarchical nanoporous structures.Finally,we will provide a brief overview of the current situation and discuss the current challenges and potential research directions in the field.

非平衡压缩实现高灵敏度、线性响应协同的离电压力传感器

Flexible pressure sensors with high sensitivity and linearity are highly desirable for robot sensing and human physiological signal detection.However,the current strategies for stabilizing axial microstructures(e.g.,micro-pyramids)are mainly susceptible to structural stiffening during compression,thereby limiting the realization of high sensitivity and linearity.Here,we report a bending-induced nonequilibrium compression process that effectively enhances the compressibility of microstructures,thereby crucially improving the efficiency of interfacial area growth of electric double layer(EDL).Based on this principle,we fabricate an iontronic flexible pressure sensor with vertical graphene(VG)array electrodes.Ultra-high sensitivity(185.09 kPa^(-1))and linearity(R^(2)=0.9999)are realized over a wide pressure range(0.49 Pa–66.67 k Pa).It also exhibits remarkable mechanical stability during compression and bending.The sensor is successfully employed in a robotic gripping task to recognize the targets of different materials and shapes based on a multilayer perception(MLP)neural network.It opens the door to realizing haptic sensing capabilities for robotic hands and prosthetic limbs.

Gravitational waves and primordial black hole productions from gluodynamics by holography

Understanding the nature of quantum chromodynamics(QCD)matter is important but challenging due to the presence of nonperturbative dynamics under extreme conditions.We construct a holographic model describing the gluon sector of QCD at finite temperatures in the non-perturbative regime.The equation of state as a function of temperature is in good accordance with the lattice QCD data.Moreover,the Polyakov loop and the gluon condensation,which are proper order parameters to capture the deconfinement phase transition,also agree quantitatively well with the lattice QCD data.We obtain a strong first-order confinement/deconfinement phase transition at Tc=276.5 Me V that is consistent with the lattice QCD prediction.Based on our model for a pure gluon hidden sector,we compute the stochastic gravitational waves and primordial black hole(PBH)productions from this confinement/deconfinement phase transition in the early Universe.The resulting stochastic gravitational-wave backgrounds are found to be within detectability in the International Pulsar Timing Array and Square Kilometre Array in the near future when the associated productions of PBHs saturate the current observational bounds on the PBH abundances from the LIGO-Virgo-Collaboration O3 data.