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An efficient surface enhanced Raman scattering(SERS)substrate was prepared by screen printing silver ink on drawing paper, white card paper and coordinate paper. The results showed that silver film/drawing paper represented the best SERS activity, followed by silver film/white card paper and silver film/coordinate paper. The minimum detection limits for crystal violet were 10-8, 10-7 and 10-7 mol·L-1, respectively. In addition, ten different positions were randomly selected on the same silver film/drawing paper surface, and the relative standard deviation values of the peak intensitiesat 913, 1 179 and 1 620 cm-1 were 13.2%, 12.5% and 10.6%, respectively, which indicated outstanding uniformity.

The efficient AgNPs/photographic surface enhanced Raman scattering(SERS) paper substrate was prepared by inkjet printing silver ink on photographic paper, for which the wettability and surface morphology were represented by contact angle meter and scanning electron microscope(SEM). The application of AgNPs/photographic paper for detecting pesticide residues was studied by simulating the residual states of thiram on peels and in juice. It was found that thiram molecules mixed in juice or on peels could be directly recognized by the substrate without any treatment. The minimum detection concentration of thiram in juice was 0.024 mg∙L-1, in which a good linear relationship between characteristic peak intensity and concentration was obtained The detection limit of thiram on the two peels was both 0.25 ng∙cm-2. In addition, ten spots were selected from the same substrate to study the uniformity randomly. The relative standard deviations of the characteristic peak intensities at 1 142 and 1377 cm-1 of thiram were 7.8% and 5.7%, respectively. The results showed that AgNPs/photographic paper substrate had great potential in the detection of pesticide residues.

An automatic recognition system of paper currency serial numbers of the Republic of China was realized by deep learning in this paper. Firstly, the characters of paper currency serial numbers of the Republic of China were extracted and segmented. Secondly, pre-processing for each character was conducted and the blank character zone was clipped in order to normalize the character size.Lastly, the characters were recognized by the convolutional neural network.The experimental results showed that the paper currency serial number recognition system proposed in the paper could reduce the workload of manual entry while there were stains and wrinkles existing on the paper currency.The recognition accuracy of a single character could reach more than 99.99%.

Organic wastewater treatment and energy recovery using microbial fuel cell（MFC） are of great significance for pollution reduction and energy saving. The bibliometric analysis of this field from 2008 to 2021 was conducted in this paper. From the two aspects of basic data analysis and hot topic words, this paper discusses the research trends in this field. The results showed that a total of 486 articles were published from 2008 to 2021. China was the country with the highest number of articles published, but had relatively low number of citation per article. According to the evolution of the subject words, the research in this field can be divided into feasibility, performance improvement, and application transformation stages, respectively. The problems to be solved include low power output, high input cost, low system stability and so on at present. Our results may provide a scientific reference for researchers in this field to understand the international progress and breakthrough point of future research, so as to boost the removal efficiency and energy utilization of organic wastewater in future.

The purpose of this paper is to investigate a class of variational inclusions with ϕ accretive type mappings in the Banach space X. We prove the existence and uniqueness of solutions to the variational inclusions and the convergence of the three-step iterations with errors. The results in this paper improve and extend the earlier results obtained by professor ZENG and et al..

The functional diversity of plants is a key factor influencing biodiversity and ecosystem functions.How to quantify the functional diversity of plants in different ecosystems is crucial to study the relationship between biodiversity and ecosystem functions.In the present paper,the concepts,the calculation methods of relevant indices of functional diversity,and the current situation about their studies in vascular plants and bryophytes were summarized.Finally,how to further conduct studies on bryophyte functional diversity were analyzed.The paper provided comparatively systematic documents concerning bryophyte functional diversity for ecologists.

Efficient direction of arrival(DOA) estimation for densely distributed targets was a difficult and hot spot in current high-precision positioning technology.There were many problems and issuesfor existing DOA estimation methods which were designed based on the compressed sensing theory,such as the difficulty of matching the discrete grids with parameters in continuous domain,the high correlation among discrete grids,and the low computational efficiency.In this paper concerning the non-ideal situation of dense DOA distribution and low signal-to-noise ratio,gridless compressed sensing dense DOA estimation methods were designed using sparse and parametric approach (SPA) algorithm and continuous compressed sensing (CCS) algorithm respectively.The performance of these two algorithms for dense DOA estimation were analyzed.The simulation experiments showed that the method designed in this paper could effectively improve the estimation precision of dense DOA.

Rare earth industry in Shanghai is mainly based on the applications of rare earth functional materials and related devices.Elaborations on 6 aspects including the current status and operation condition of rare earth industry in Shanghai were made in this paper,and the paper also discusses in detail about how to realize its high-quality development,and offers some suggestions in confrontation with the opportunities and challenges.

This paper elaborated the working mechanism,communication mode and application of mobile ad hoc network.Besides,it analyzed the greedy perimeter stateless routing (GPSR) protocol based on geographic location.For the reason that the GPSR protocol may result in a higher packet loss rate because of high relative speed,this paper modified and implemented the improved greedy perimeter stateless routing (IGPSR) algorithm which took into account the speed and direction of the source nodes,destination nodes,and alternative relay nodes.The position of the node could be calculated and predicted with the current speed of the node,thus the best relay node was identified.Simulation experiments showed that the IGPSR routing protocol had a lower packet loss rate than the GPSR routing protocol when nodes moving at high speed.

During the last few years, the study on the existence of nontrivial solutions for nonlinear algebraic equations or nonlinear systems of algebraic equations has attracted much attention of some researchers, and some interesting results have been obtained. In this paper, we apply a well-known fixed point theorem to study the existence of positive solutions to a nonlinear system of algebraic equations. Moreover, the eigenvalue intervals are also characterized by using the behaviors of the nonlinear term at the origin and at the infinity. Compared to those in the literature, the methods used in this paper are much easier, and our new results generalize and improve those existed results.

Today, more than 95% of chemical products are manufactured through catalytic processes, and the development of more efficient catalytic materials has become the focus of many researchers. Metal organic frameworks（MOFs） mediated structures（MOFMSs） derived from MOFs retain most of the MOFs parent’s properties, such as high porosity, structural tunability, and high metal loading rate, providing opportunities for the rational design of novel solid catalysts. In this paper, we classify MOFs precursors according to metal nodes, review the recent progress of MOFMSs in heterogeneous catalysis, and present our personal views on the future research directions of MOFMSs.

According to field investigations in grotto temples， the layered cracks on the roof have a remarkable impact on the structural safety and artistic value， which has become an important link in cultural relics. A novel methodology to extract and classify layered cracks’ target contour efficiently is presented in this paper. Firstly the ordered point cloud is mapped into a 2D depth map using the elevation difference. Secondly， image processing and morphological methods are combined to estimate the target cracks. Finally， a verification test was conducted for a regular Buddha base in No. 32 grotto North Qingyang Grotto Temple to check the method’s accuracy， and a fair value of 98.69% was reached. Besides， a case study was conducted for natural layered cracks on the roof， which suggested that the proposed method is versatile to provide critical characteristics （e.g.， length， trend and surface area） of layered cracks and make the risk rating as well as providing project protection suggestion.

In this paper， we consider the spherically symmetric solutionstothe field equation of Rastall gravity in the background of positive pressure matter.Firstly，we study the spherically symmetric solution in Rastall gravityin the background of matter with zero pressure uniformly distributed. An analytical solution is obtained as λ=2/3， the time component of which is a constant， and the radial component of which is a function of r. This solution can describe a "dust sphere" in the four-dimensional spacetime. Secondly， we investigate the numerical solution of the Rastall gravitational field equation and the equation describing the relationship between the energy-momentum tensor and the Ricci scalar in the background of positive pressure matter arbitrarily distributed. The numerical results show that the spherically symmetrical gravitational potential is extremely complicated. Fortunately， the time and space components of the gravitational potential tend to 1 as r approaches infinity.

In this paper， the optimal control problem of the single-input multi-variable system is designed. The dynamic constraints are the n-order exponentially damped oscillators， and the necessary conditions for the optimality of the exponentially damped oscillators are obtained. Taking the optimal control problem of the exponentially damped oscillators of single degree of freedom as an example， a set of internal variables are used to solve the two-point boundary value problem， and the necessary conditions for the optimality of the exponentially damped oscillators of single degree of freedom are obtained. The numerical simulation results show the above control design well.

Allen-Cahn equation is an important phase field model, which has been widely used to investigate interfacial dynamic problems. In this paper, we propose a Legendre-Gauss spectral collocation scheme for the Allen-Cahn equation by using Legendre-Gauss-Lobatto nodes as the collocation points in both the time and the space directions. We use the fixed point iteration method to solve the resulted nonlinear system. Ample numerical results demonstrate the efficiency of our new method.

In this paper, we introduce the lower dimensional Busemann-Petty problem on the entropy of log-concave functions: for two even log-concave functions f and g with positive and finite integrals in Rn, if ∫Rn∩Hf(x)dx is smaller than Rn∩Hg(x)dx for every i-dimensional subspace H, whether the entropy of f is larger than the entropy of g? Furthermore, partial answers to this problem are given, which might provide a new path to study the long-standing lower dimensional Busemann-Petty problem on convex bodies.

Let G = GL2(C), and let B be the standard Borel subgroup of G, and let CG (resp. CB) be the group algebra of G (resp. B) over the field of complex numbers. For any character θ of B, define the naive induced module M(θ) = CG×CBθ. In this paper, we prove that if θ is antidominant, then M(θ) is irreducible. Thus, we give a class of new infinite-dimensional irreducible representations of GL2(C).

In this paper， a nano-zero valent iron（nZVI）-polylactic acid（PLA）-biochar（BC） composite with sodium lignosulfonate（SL） as a surface modifier was prepared by a two-step ball milling method. Its hydrophilicity and sustained-release carbon capacity were characterized， and its performance on enhancing biological reductive dechlorination of chlorinated hydrocarbons（CHCs） in groundwater was studied. Moreover， its optimal composition ratio was also determined. The results showed that this iron-carbon composite had good hydrophilicity and sustained-release carbon capacity， and the carbon release amount tended to be stable after 72 h. The material can effectively dechlorinate 1，1，1-trichloroethane（1，1，1-TCA） coupling with dissimilatory iron reducing bacteria. The maximum removal rate of the pollutant in system reached 85.00% within 168 h， and the maximum degradation rate was 6.74 mg·L-1·h-1. The degradation effect increased with the increase of zero-valent iron（ZVI） and PLA content. Considering carbon releasing capacity， degradation effect and preparation cost， the optimal mass ratio of BC， PLA and nano zero-valent iron was 3∶1∶1. The main pathways of 1，1，1-TCA removal by this composite were the instant chemical reductive dichlorination induced via zero-valent iron and the long-term biological reductive dechlorination induced via dissimilatory iron reducing bacteria. The results in this study were expected to provide innovative technical supports for the remediation of groundwater contaminated with CHCs.

As an important part of image processing and computer vision,image classification can analyze and manage digital images quickly and accurately.This paper studies the classification problem based on bag of word (BOW)model and learns the relationship between image similarities in image comprehension.Then,this paper proposes a maximum-interval Nearest Neighbor classification algorithm.By learning the pair-wise constraint metric and adding the constraint of the original spatial data classification to the optimal target.This paper learns a distance function which can reflect the current sample data and uses this function to construct the classifier according to the k-NearestNeighbor(KNN) classifier.Compared with the traditional Euclidean distance algorithm,the classifier based on metric learning has higher correct rate than the traditional one based on the experiments on several international standard image datasets.

In order to enable the cyclist to keep abreast of the road conditions behind him without looking back when changing lanes or turning at an intersection, a bicycle rear-view system for riders was designed to sense the potential rear dangerous factors, such as the high-speed cycle which was going to overtake the rider on the left or right, to improve safety. This system could be divided into two parts:the detection system and the reaction gloves. The detection system described in this paper was constructed with USB camera as the main data acquisition sensor and the executive mechanism, as well as you only look once(YOLO) v4 as the main vision recognition algorithm. By installing the camera at the rear of the bicycle and transmitting the information wirelessly to the special gloves, the rider could be effectively informed with the emergency detected, and then take precautions immediately. The experimental results showed that the constructed system was able to detect the moving rear-vehicles with considerable accuracy within a safe distance, select the most threatening targets, and display on the gloves.

In order to resolve the problems of imperfect ball picking mechanism and poor adaptability of table tennis recognition algorithm, this paper proposes an intelligent table tennis ball picking machine based on visual recognition. We use the Raspberry Pi 4B demo board as the control unit, and recognize the table tennis by the lightly modified you only look once (YOLO) v5s algorithm, and roll the table tennis into the storage basket through the fan-blade type ball collection mechanism. Experimental results show that under the condition that the number of table tennis balls is less than 150, the recognition accuracy and completion rate of the ball picking machine can reach more than 95%, and the missed detection rate is less than 7%. At the same time, the structure of the ball collection mechanism is simple, reliable and efficient, and the overall design scheme has good practical application value.

Light field (LF) information had high-dimensional characteristics. The spatial information required in the reconstruction task was highly coupled with the angular information in the macro pixel map. To fully utilize the spatial angular information to improve the quality of super-resolution (SR) reconstruction, an improved LF image angular SR reconstruction network based on the LF spatial angular decoupling mechanism was proposed. Considering the influence of different features in the image on the reconstruction quality, the degree of influence from different features is modified by different channel assignment mechanisms to improve the reconstruction accuracy, and the attention mechanism was introduced to obtain richer spatial angle information while stacking feature extraction layers. The results of the experiments on the test scenes showed that the reconstruction network proposed in this paper had a better reconstruction effect on both synthetic and real scenes. The peak signal to noise ratio/structural similarity (PSNR/SIM) values were 34.62/0.964 and 42.68/0.972 on the two synthetic scene data sets, and the average PSNR/SIM values on the real scene were 39.67/0.990.

An electromagnetic inverse scattering algorithm was proposed based on the improved U-Net(M-Net) model in this paper. M-Net model was mainly composed of multi-scale input layer, U-type convolutional neural network (CNN) and multi-scale mean output layer. By using the scattering field data as the network input, it could ensure the calculation accuracy and efficiency, and reduce the workload of manual calculation. The simulation experiments with the two-dimensional dielectric as the reconstruction target showed that the M-Net model had high efficiency in solving the electromagnetic inverse scattering problem and resulted in less error comparing with the U-Net model.

The intelligent reflective surface (RIS) used low-cost passive reflective elements to control the phase of incident signal, which could enhance wireless coverage range and improve channel capacity in the sixth-generation mobile communication system. Since the dispersion environment of the RIS-assisted millimeter wave multiple input multiple output (MIMO) cascaded channel only had a few paths with corresponding spatial angles and loss, the non-grid atomic norm minimization method was proposed to estimate the angle of departure at base station and the angle of arrival at user equipment on downlink in this paper. The angle estimation problem was converted into convex optimization models for solution. Simulation results showed that accurate angles could be obtained only with a small number of snapshots.

Based on learner ability, a deep knowledge tracing (DKT) algorithm was proposed with attention mechanism, aiming at the lack of attention paid to early knowledge points by DKT based on recurrent neural network(RNN) and long-short term memory(LSTM) network. A more balanced and objective weight distribution model of knowledge memory degree for learners with different abilities was established by time slot clustering method. The experimental results on common public datasets showed that this model proposed was superior to two benchmark models and two comparison models, which demonstrated that the model proposed in this paper could represent the state of learner knowledge better.

Selection of the hyper-parameters is critical to the performance of Least Squares Support Vector Machines (LSSVM),directly impacting the generalization and regression efficacy of the LSSVM.In order to solve the problem above,this paper based on ABC has done certain researches and improvement (IIABC) which have been applied to the LSSVM regression analysis.In this paper,the Artificial Bee Colony (ABC) Algorithm is improved,introducing a new cross processing method,studying a ABC based on double population policy,and putting forward a run-time parameter adjustment method,and then the robustness and accuracy of the optimized IIABC are verified.Experiment adopts MAPE as the benchmark IIABC algorithm for gas regression analysis,and shows that forecasting based on the IIABC-LSSVM is of higher accuracy than the IABC-LSSVM.

In space information network,satellites are connected through inter satellite links.High-queuing-delay,which is caused by the restriction of the spatial network node and the dynamic network topology as well as the intermittent connectivity of communication link,is often observed among spatial network node.It means that network congestion and even packet loss occurs and results in low reliability of data transmission.Aiming at realizing network congestion monitoring efficiently and accurately,this paper analyses the sparsity of links in space information network,and the link state detection is modeled as a compressed sensing problem.Based on greedy algorithm,the paper obtains the link delay and the location of congestion links.Numerical results show that the algorithm can recover the link delay with high accuracy in the case of less sample data.

In this paper,considering time-frequency doubly selective channel,we utilize the channel's time correlation that the channel coefficientscorresponding tothe neighboring instants have a strong correlation.And we present a linear approximation method,which effectively reduces the number of unknown parameters.Considering the sparseness of the wireless channel in the delay domain,this paper reconstructs unknown channel parameters of the proposed model based on compressed sensing (CS) theory.In the simulations,we observe the system performance of the linear approximation model and the non-linear approximation model,respectively,and present the normalized mean squared error (NMSE) curves based on the least square (LS),orthogonal matching pursuit (OMP) and sparse Bayesian learning (SBL) algorithms.Simulation results show that the linear approximation method can effectively model the time-frequency doubly-selective channels.For the proposed linear approximation model,SBL algorithm can accurately recover the channel response,and overcome the Doppler effecteffectively.

This paper is devoted to the convergence analysis of a threestep hybrid viscosity approximation method for finding a common fixed point of a countable family {Tn}n≥1 of uniformly Lipschitz pseudocontractions in a real Hilbert space.Without uniformly closed condition of {Tn}n≥1,we establish some strong convergence theorems for this method.The results presented in this paper improve and extend the corresponding results in the earlier and recent literature.

In order to acquire the Deep Web data source information maximally,and classify the data source information effectively,this paper proposes a method of Deep Web data search framework based on the real-time database to facilitate the subsequent data source integration work and the user′s retrieval.The framework designs and installs the S_DS Application module on the local server,the retrieved website installs the C_DS Application module by searching and downloading to achieve the data information connection and real-time transmission.In this framework of the real-time query,in order to ensure retrieval efficiency,this paper uses the classification method combined with Hownet and Tongyici cilin to classify each big retrieved web site.

In this paper,by analyzing and comparing of the traditional web method of session identification,with the improvement on the most commonly used method of session identification based on time threshold,this paper proposed a session identification method based on dynamic threshold,in which the algorithm uses the average time interval between request records in conversation of dynamic calculation,and in combination of the average size of dynamic calculation session pages dynamically adjusts the threshold according to the characteristics of users and Webpage.Compared with the traditional single a priori threshold,this method can generate dynamic threshold according to different user access to different pages and make full use of user information and Webpage.After experimental verification,this method can identify more user sessions.The accuracy of session identification and the recall rate are higher than the traditional algorithm.

Traditional separation technologies of low-carbon hydrocarbon gases such as cryogenic distillation and solvent extraction have high energy consumption and are easy to cause certain environmental pressure. In addition, due to the development of industry and technology and the higher requirements for products（such as purity）, traditional separation methods can no longer meet the demand. As a relatively novel class of porous organic-inorganic hybrid materials, metal-organic frameworks（MOFs） have received extensive attention in the field of low-carbon hydrocarbon separation and purification due to their controllable topological structure and diverse chemical microenvironment. In this paper, the characteristics of MOFs as adsorbents for the separation and purification of low carbon hydrocarbon gases are summarized, and the application progress of MOFs materials in the separation of alkynes/alkenes is emphasized.

Metal phthalocyanine（MPcs） can be used for purification, factory drainage, agricultural drainage, etc. It is an excellent environmental protection material. This paper summarizes the structure, characteristics and synthesis methods of MPcs, introduces the principle of its photocatalysis, summarizes its research progress in photocatalysis, focuses on its applications in the degradation of dyes rhodamine B, methyl orange（MO）, methylene blue, tetracycline antibiotics, sulfonamide antibiotics, β-lactam antibiotics, and points out the prospect of MPcs in the related work of photocatalysis in the future.

In recent years, the environmental problems brought by the rapid development of industrialization have attracted extensive attention. Phenol containing wastewater is the main organic pollutant wastewater in papermaking, pharmaceutical, petrochemical and other industrial productions. Due to its high toxicity and difficult biodegradation, it is urgent to develop some wastewater treatment processes that can degrade it efficiently. This paper focuses on the principle of microbial fuel cell（MFC） technology, its application in the treatment of phenol containing wastewater and several factors affecting its performance,and points out the research direction of MFC technology in the future.

As a key factor in the preparation of highly active heterogeneous catalysts containing a small amount of rare metal elements, catalytic support effect has been widely studied. Recently, the support effect of metal-organic frameworks（MOFs）has been investigated by using their wide adjustability in pore size, electronic state, andselective adsorption property. The current reports on heterogeneous catalysis of metal nanoparticle（NPs） supported MOFs（M/MOFs） clearly shows that MOFs support can greatly enhance the catalytic activity and adjust the selectivity of products through the carrier effect, and using MOFs as a carrier will be conducive to the preparation of new high-performance catalysts with metal nanoparticles. In this paper, three types of support effects, namely molecular sieving, charge transfer, and substrate adsorption effects, were reported, and their applications on M/MOFs composite catalysts were also reported.

Polyoxometallates（POMs）, also known as metal oxygen clusters, can be used for diagnosis and therapy of cancer due to the diversity of its structure and properties. However, the high toxicity and in vivo dissociation of POMs limit their further clinical application. In recent years, the assembly of POMs and organic molecules/polymers into hybrid POM nanomaterials has become one of the research hot topics. Inorganic-organic hybrid POM nanocomposites can not only improve the stability and biocompatibility of POMs, but also improve their cell penetration ability and tumor targeting（EPR effect）, showing broad application prospects in tumor diagnosis and treatment. In this paper, we briefly summarize the application of POM nanomaterials in the diagnosis and therapy of cancer, including magnetic resonance imaging（MRI）, photoacoustic imaging（PAI）,photothermal therapy（PTT）, chemodynamic therapy（CDT）, radiotherapy （RT） and multi-mode image-guided combination therapy.

Vinyl acetate（VAc） is an important chemical raw material and widely used in coatings, adhesives, sizing, vinylon, film, leather processing, pharmaceutical and other fields. In this paper, the research progress on the synthetic routes of VAc is reviewed and discussed. At present, the main route at home and abroad is ethylene process and acetylene process. Ethylene process is relatively clean, but the catalyst of which is too expensive and easy to deactivate. In spite of the safety risks of explosion and the low catalytic efficiency of the acetylene process, it is still more suitable for China because of the abundant reserves of calcium carbide.

Calcium phosphate is the main component of inorganic matter in human bone tissue, and silicon（Si） has been proved to have an effect on inducing bone formation. Therefore, silicon-containing calcium phosphate has been widely studied as a bone defect repair material. In this paper, nano Si-apatite powder was synthesized by a hydrothermal method, using calcium nitrate tetrahydrate（Ca（NO3）2·4H2O）, ammonium phosphate dibasic（（NH4）2HPO4）, and tetraethyl orthosilicate（TEOS） as calcium（Ca） source, phosphorus（P） source, and silicon source, respectively. In addition, cetyltrimethylammonium bromide（CTAB） was used as a surfactant and the effect of CTAB amount on the chemical composition, crystal structure, and morphology of the synthesized Si-apatite powder was studied. The results indicated that the addition of CTAB could not only reduce the particle size of nano Si-apatite, but also promote Si element entering the apatite lattice, improving the Si content in Si-apatite. When the addition amount of CTAB is 0.55 g, the mole ratio of n（Ca）∶n（P）∶n（Si） in the synthesized Si-apatite could reach 5∶2∶1. After calcination at high temperature, this nano Si-apatite powder was easier to form the orthogonal silicon-calcium phosphate（Ca5（PO4）2SiO4, CPS） phase.

The two-dimensional（2D） organic frames of metal phthalocyanines（MPcs） have wide application value in adsorption and separation, catalysis, biochemistry and so on. The synthesis and research of 2D frames based on MPcs provide a new way to develop new multifunctional materials with electrical, magnetic, optical, and electrochemical properties. In this paper, firstly, the structure-function relationship of metal phthalocyanine monomers for constructing 2D organic framework and the historical development and unique functions of 2D organic framework materials are introduced. Secondly, the synthesis methods of metal-phthalocyanines 2D metal-organic framework materials（MPcs-2D MOFs） and metal-phthalocyanines 2D covalent organic framework materials（MPcs-2D COFs） were introduced. Finally, their applications in sensor, catalysis, energy storage, and photodynamic therapy are summarized.

As a downstream product of turpentine that has deep processed, borneol is widely used in medicine, flavors and fragrances, daily chemicals. However, natural borneol resources are limited. At present, synthetic borneol has some disadvantages such as low yield, low product quality, and environmental pollution. In this paper, the synthesis methods and applications of borneol are reviewed. Furthermore, esterification-saponification method that is widely used in the industry and its catalysts are systematically summarized. In order to improve the yield of synthetic borneol and reduce the isoborneol content of isomers with certain side effects, extensive and in-depth research has been carried out on the catalysts used in the esterification process. The catalysts are mainly boron-containing, titanium-containing, boron-containing titanium composites, solid superacids, and ionic liquids, etc.

The emission of various nitrogen-containing pollutants in cities causes various hazards in the environment. Clarifying the source and circulation law of nitrogen pollution can provide a series of supports for environmental governance. In this paper, not only the mechanism and harm of nitrogen pollution but also the status and types of nitrogen pollution in urban water environment were described. The latest progress in the research on the traceability of nitrogen pollution in urban water was reviewed. The surface waters were mainly affected by total nitrogen, nitrate nitrogen, and ammonia nitrogen pollutions. Most of the water environment only met the class Ⅳ-Ⅴ water quality standards, and human activities were the main contributor to the nitrogen pollution in urban water environment. In addition, the source tracing technology of nitrogen pollution in water （hydrochemistry analysis, isotope tracing, microbial source tracing, isotope source analytical model, etc.） and the characteristic values of nitrate-nitrogen and oxygen isotopes in end-member substances were further summarized, which provided a reliable way to trace the source of nitrogen pollution and clarify the migration law of nitrogen pollution. This review is of great significance for the traceability and prevention of nitrogen pollution in urban water environment.

On a large spatial scale, investigation and clarification of geographical distribution pattern of moss diversity in China is of significance for overall arrangement in relation to diversity reserves. In this paper, the floristic data of 1 534 moss species from 80 reserves and national forest parks in the eastern China were collected. Based on these data, the nested level of mosses and their main categories among 80 geographical units, and the SLOSS (single large or several small) strategies were analyzed. The results indicated that significant nested distribution patterns were found in mosses (as a whole), pleurocarpous mosses, acrocarpous mosses, Buxbaumiidae-Polytrichidae mosses, Spagnaceae, Pottiaceae, Brachytheciaceae, Orthotrichaceae, Dicranaceae and Bryaceae by using either matrix temperaute or NODF metrics, with a significance value at P

Plant growth promoting rhizobacteria (PGPR) is a kind of natural soil bacterias that can significantly improve plant physiological indexes and control plant diseases. PGPR can play a direct or indirect mechanism of actions through nitrogen fixation, phosphorus dissolution, siderophores secretion, plant hormone production, antibacterial substances secretion and inducing systemic resistance. PGPR can replace organic fertilizers to a large extent, and PGPR can significantly increase the nitrogen, phosphorus and potassium contents in pepper (Capsicum annuum L.) plants during pepper cultivation, thereby increasing the plant height, root length, dry weight and fresh weight of the plants. Pepper treated by root irrigation with PGPR can effectively decrease its diseases and increase its yield. This paper discussed the mechanism of PGPRand its application in pepper field cultivation, and the application potential of PGPR was also discussed, which can provid new ideas for the development of ecological agriculture.

Ammonium nitrogen transporters (AMT) are responsible for the absorption and transportation of ammonium nitrogen, and also play important roles in plant growth and development. In this paper, the SoAMT gene family members were identified in the spinach genome, and their expression patterns were analyzed. Results showed that there were six SoAMT members in spinach genome, including five AMT1 and one AMT2, which were mainly distributed on 1, 4, 5, and 6 chromosomes. The length of their coding regions ranged from 1 443 to 1 506 bp. All SoAMT members had the unique conserved domains and conserved motifs of the AMT gene family, and 9-11 trans-membrane domains. Their promoters contained many elements about jasmonic acid response, anaerobic stress response, and so on. The SoAMT genes were expressed in roots, leaf blades, and petioles. Most SoAMT1 genes were induced by nitrogen deficiency, nitrate nitrogen, or ammonium nitrogen, while SoAMT2 expression was inhibited by ammonium nitrogen. The obviously different nitrogen response patterns between two types of subfamily members might be related to their different roles in response to nitrogen changes.

In this paper, we conducted a study of the growth of 18 varieties of roses (Rosa chinensis Jacq.) in 15 representative parks and roads in late summer and early autumn, when the roses are in full bloom. The results showed that it is better suited for Shanghai to plant heat and humidity tolerant varieties such as "Wonderland" and "Angela", and that they are already planted on large scale both in quantity and in area. However, the promotion of cherished varieties needs to be improved. Secondly, soil nutrients and diseases have a significant impact on the growth of roses, and most of the habitats in the green belts are unsatisfied, with low soil fertility and high rates of disease spread between plants in this season, such as black spot. We hope that the present study will provide a data background for further strengthening of key technical studies such as screening, breeding and configuration studies of suitable colourful and precious rose varieties in the future.

Lysin motif (LysM) is a ubiquitous domain in multiple proteins. LysM-containing proteins in plants have the ability of sensing chitin or its oligosaccharides, thereby initiating plant immune responses to pathogens. During the immune response process in plants such as rice and Arabidopsis, LysM-containing proteins work as an important pattern recognition receptor through diverse forms of oligomerization, and then trigger cytoplasmic receptor-like kinases, and mitogen activated protein kinase (MAPK) cascades for signal transduction. Meanwhile, reversible protein phosphorylation and protein degradation pathway could negatively regulate the LysM-containing proteins-mediated defense signal transduction. This paper reviews the molecular mechanism underlying the LysM-mediated signal transduction implemented during plant immunity.

In the traditional mode,colleges use paper application form to apply for visiting abroad.This process is very complicated and takes a long time.What′s more,the audit results is not timely feedback,existing data cannot be shared,and the data are not easy to be calculated,etc.To solve the above problems,this paper introduces workflow engine,based on the Primeton Business Process Suite,the College Management Platform of application for visiting abroad is developed which can solve the operation and monitoring issues of application and review processes.Meanwhile,several elements in designing flow chart is stated combining with the platform,which include:branch,polymerization,participants,work items.After development and on-line use,it is proved that the platform can reduce labor costs,improve software quality,enhance the user experience,and effectively improve the efficiency of various departments.

A document information system based on Montague semantics(MS)and controlled natural languages(CNL)can be both symbolized and normalized-the two characteristics possessed by traditional document classification systems and thesaurus indexing systems,respectively;it can also realize complicated syntax and semantics functions,so as to improve the efficiency of document information retrievals greatly.Moreover,it can form standard paper abstracts automatically and realize translations between different languages.This paper attempted to construct such a kind of system,which includes category classification of words,expressions of sentence functions,maps/translations between natural and formal languages,as well as between Chinese and English languages.Finally,an application program was designed to test functions of the system.The results of this study show that the data structure and function simplementation of the proposed information system based on new concepts are feasible.

In this paper,the IDMA technology is studied in complicated time-variant multipath channels.A theoretical derivation of iterative process in the receiver which is suitable for WBAN transmission property will be given based on central-limit theorem.By the methodology combing theoretical synthesis and computational simulation,a comprehensive research focusing the necessity,feasibility and system performance analysis of the IDMA integrated WBAN is conducted in this paper.

This paper studies a new fractionally spaced equalization scheme to solve the problem of timing offset existing in the traditional MLSE equalization technology,in GMSK modulated system.The algorithm structure of this scheme is not based the traditional structure which include a matched filter,a whitening filter,but based on the improved Viterbi algorithm (MVA).This new scheme gives a better solution to the problem of timing offset sensitivity faced by the traditional MLSE equalization.The simulation analysis shows that,compared to the traditional MLSE,this novel fractionally spaced equalization scheme proposed in the paper can effectively improve the equalization effect,enhance the system performance and show better results under co-channel interference.