Recent Advance in Synaptic Plasticity Modulation Techniques for Neuromorphic Applications

Manipulating the expression of synaptic plasticity of neuromorphic devices provides fascinating opportunities to develop hardware platforms for artifi-cial intelligence.However,great efforts have been devoted to exploring biomimetic mechanisms of plasticity simulation in the last few years.Recent progress in various plasticity modulation techniques has pushed the research of synaptic electronics from static plasticity simulation to dynamic plasticity modulation,improving the accuracy of neuromorphic computing and providing strategies for implementing neuromorphic sensing functions.Herein,several fascinating strategies for synap-tic plasticity modulation through chemical techniques,device structure design,and physical signal sensing are reviewed.For chemical techniques,the underly-ing mechanisms for the modification of functional materials were clarified and its effect on the expression of synaptic plasticity was also highlighted.Based on device structure design,the reconfigurable operation of neuromorphic devices was well demonstrated to achieve programmable neuromorphic functions.Besides,integrating the sensory units with neuromorphic processing circuits paved a new way to achieve human-like intelligent perception under the modulation of physical signals such as light,strain,and temperature.Finally,considering that the relevant technology is still in the basic exploration stage,some prospects or development suggestions are put forward to promote the development of neuromorphic devices.

Study on Planting Techniques of Medicinal Plant Anchusa italica Retz

Anchusa italica Retz.,a perennial herb,has the effects of clearing away heat and toxic materials,and killing parasites to relieve itching.It is mainly used for breast abscess,sore swollen poison,scabies and so on,and serves as one of the commonly used medicinal materials in Uygur medicine.A.italica is distributed in Iran,Europe,Afghanistan and Kazakhstan.It is cultivated in China,and Xinjiang mostly imports it from Pakistan.This study belongs to the technical field of traditional Chinese medicine planting.The planting method solves the technical problems of sowing,field management,harvesting and processing of A.italica.

Advances Treatment Technologies in Chemical Industry Wastewater

The main treatment methods of chemical wastewater were reviewed.Physical,chemical,and biochemical treatment technologies effective for removing those pollutants were presented with their applicability,effectiveness and advantages.The problems facing the wastewater treatment in the petroleum chemical industry and coal chemical industry were introduced.In the end,the new progress and trend of the processes were overviewed.

Efficiencies of Chemical Techniques for Rice Grain Freshness Analysis

Two chemical methods which are commonly used for rice grain freshness determination were investigated for their efficiencies. Method 1 is made of bromothymol blue indicator, and the principle is based on indicator＇s color which is changed in according to pH of the stored rice grains. Method 2 is based on peroxidase activity which deteriorates during storage of rice grains. Both methods were used for determination of fresh-aged rice index of six Thai-rice cultivars, four from non-waxy rice cultivars （KDML 105, Chai Nat 1, Chai Nat 2 and Phitsanulok 2） and two from waxy rice cultivars （San-pah-tawng and RD6）. Rice samples were kept in the forms of paddy and polished rice. Fresh-aged rice indices were determined using both methods every two weeks over the storage period of 24 weeks （six months）. It was found that both methods were capable of detecting fresh-aged rice indices. The color of chemical solutions changed with regards to the age of rice grains and it could be detected spectrophotometrically. Rice grains which have been kept as paddy provided more consistent results. Method 1 is recommended for industrial application as it is simple, efficient and inexpensive.

Effects of DPC on Agronomic Traits and Economic Characters of Machine-Harvested Cotton in the Yellow River Valley of China and Chemical Control Techniques

[Objective] The aim was to investigate the effects of DPC chemical controlling technique on agronomic traits, yield and quality of machine-harvested cotton in the Yellow River Valley of China, and clarify the reasonable control period and the application amount of DPC. [Method] The new machine-harvested cotton variety Hengmian HD008 was used as the test material, and 3 different DPC treatments were set. [Result] DPC significantly reduced plant height and branch length, reduced branch angle and leaf area, so the rational control can effectively shape the ideal plant type of machine-harvested cotton. DPC had significant effects on yield and yield components, and the proper amount of DPC could increase the number of bolls during hot days, the number bolls in autumn and the total number of bolls. It increased the boll weight and seed index, but decreased lint percentage decreased, and proper amount of DPC could increase the yield. DPC significantly increased the specific breaking strength of fibers, and proper control could improve the uniformity of fibers, but other indexes had no significant influence. [Conclusion] According to the requirements of machine harvest to the agronomic traits of cotton and the growth characteristics of cotton plant, chemical control could begin after floral bud emergence in cotton about every 10 d, and the spraying amount can be controlled according to the growth amount of the main stem. The daily growth amount of plant height should be controlled at 1.5-1.8 cm, and the plant height should be within 75-90 cm.

Application of Chemical Tracing Experiment Technique in Leakage Detection of Hydraulic Engineering

[Objective] The research aimed to study the application of chemical tracing experiment technique in leakage detection of hydraulic engineering.[Method] According to the current situation of Sanyuan Western Suburb Reservoir in Xianyang City of Shaanxi Province,three sections （L1,L2 and L3） were set.KI was selected as the chemical tracer to carry out the tracing and detection research.[Result] There was no obvious leakage phenomenon in L1,L2 and L3 sections.The impermeability of rock in some dam abutments was bad.[Conclusion] The leakage reason of Western Suburb Reservoir was that the impermeability of rock in some dam abutments couldn’t satisfy seepage requirement.After the reservoir was put into operation,the water level in front of dam rose,and the ground water level of dam abutment also rose.The penetration water pressure correspondingly increased,and the water content of bank slope at the downstream of dam increased.

Fabrication of Chemically-Modified Electrode Containing 1:12 Phosphomolybdic Anions by Sol-Gel Technique and Its Electrocatalytic Reduction of BrO_3 ^-Anions

A novel chedrically-modified electrode containing 1:12 phosphomolybdic anions wasachieved on the surface of platinum electrode by the sol-gel technique. The electrode exhibits ahigh catalytic activity towards the electroreduction of BrO3- anions.

Technique of Seedling Broadcasting with chemical treated seedlings

The technique of Seedling Broadcating was first re-ported in Japan in 1970’s and introduced to China1980’s.However,it was not effectively popularizedin rice production mainly because of the require-ments of special facilities and limitation of seedlingage.Since the method could significantly save la-bor and time,a study of rice Seedling Broad-

Reliability Based Analysis of Ground Improvement Using a Polymeric Chemical Stabilizer

In view of the challenges posed by the nature of expansive soil to structural stability which makes it necessary in some cases to improve the soils before structures can be placed on them, there is a need to investigate modern trends in ground improvement techniques in order to determine their reliability. This study is thus aimed at using the reliability based approach to analyze the use of polyvinyl alcohol (PVA) in combination with 1,2,3,4 Butane-tetracarboxylic acid (BTCA) for ground improvement. This study is necessary given the challenges posed by the nature of expansive soil to structural stability which makes it necessary in some cases to improve the soils before structures can be placed on them. Simplex lattice design was employed to build the design of experiment before experimental investigations were carried out on the PVA-BTCA treated soft soils. Reliability indices were computed on the basis of the 28th day unconfined compressive strength (UCS) of the treated soil. Reliability index models were developed using the Scheffe’s technique and optimized using excel solver. From analysis of results, reliability model developed proved adequate at 5% level of significance. PVA-BTCA combination provided a potential reliability or probability of success of 99.936% at components combination of: 98.4256% for soil, 1.2352% for PVA, 0.3392% for BTCA and 15.9934% for water. It was therefore recommended that financial implications of using PVA-BTCA for stabilization be compared to those of conventional methods, in order to compare their performance-cost ratio.

Two-point Dixon and six-point Dixon magnetic resonance techniques in the detection,quantification and grading of hepatic steatosis

BACKGROUND Hepatic steatosis is a very common problem worldwide.AIM To assess the performance of two-and six-point Dixon magnetic resonance(MR)techniques in the detection,quantification and grading of hepatic steatosis.METHODS A single-center retrospective study was performed in 62 patients with suspected parenchymal liver disease.MR sequences included two-point Dixon,six-point Dixon,MR spectroscopy(MRS)and MR elastography.Fat fraction(FF)estimates on the Dixon techniques were compared to the MRS-proton density FF(PDFF).Statistical tests used included Pearson’s correlation and receiver operating characteristic.RESULTS FF estimates on the Dixon techniques showed excellent correlation(≥0.95)with MRS-PDFF,and excellent accuracy[area under the receiver operating characteristic(AUROC)≥0.95]in:(1)Detecting steatosis;and(2)Grading severe steatosis,(P<0.001).In iron overload,two-point Dixon was not evaluable due to confounding T2*effects.FF estimates on six-point Dixon vs MRS-PDFF showed a moderate correlation(0.82)in iron overload vs an excellent correlation(0.97)without iron overload,(P<0.03).The accuracy of six-point Dixon in grading mild steatosis improved(AUROC:0.59 to 0.99)when iron overload cases were excluded.The excellent correlation(>0.9)between the Dixon techniques vs MRSPDFF did not change in the presence of liver fibrosis(P<0.01).CONCLUSION Dixon techniques performed satisfactorily for the evaluation of hepatic steatosis but with exceptions.

Effects of Tobacco Curing on Accumulation of Chemical Components and Aroma Components in Tobaccos

[Objective]The aim was to explore effects of curing technique parameters on chemical components and aromatic material accumulation to formulate a suitable curing technique and for and to achieve tobacco scalding, drying and giving aromat- ic flavor. [Method] With tobacco variety KRK 26 as test materials, the test involved parameters of three curing-techniques in down, middle and upper parts of flue-cured tobaccos in an oven to measure chemical components and aromatic substances in tobaccos. [Result] The effects of curing techniques on total sugar and reducing sug- ar differed upon temperature and humidity. The contents of chemical components, such as total alkaloid, total N and the ratio of sugar/ alkali by moderate temperature and high humidity technique were of significant differences with those by moderate temperature and moderate humidity technique and with low temperature and low hu- midity technique; the chemical components by moderate temperature and moderate humidity were of insignificant differences with the treatment by low temperature and low humidity technique. Total amount of aroma components by different curing tech- niques from high to low was the treatment by low temperature and low humidity technique （461.72 μg/g）, the treatment by moderate temperature and moderate hu- midity technique （450.06μg/g） and the treatment by moderate temperature and high humidity technique （385.12μg/g）, suggesting the content of aromatic substances is high at low temperature and low humidity. [Conclusion] Moderate temperature and high humidity curing technique has significant effects on total alkaloid, total N and the ratio of sugar/ alkali of tobaccos and different curing techniques also affect the total amount of aromatic substances of flue-cured tobaccos.

Simplifying Stochastic Mathematical Models of Biochemical Systems

Stochastic modeling of biochemical reactions taking place at the cellular level has become the subject of intense research in recent years. Molecular interactions in a single cell exhibit random fluctuations. These fluctuations may be significant when small populations of some reacting species are present and then a stochastic description of the cellular dynamics is required. Often, the biochemically reacting systems encountered in applications consist of many species interacting through many reaction channels. Also, the dynamics of such systems is typically non-linear and presents multiple time-scales. Consequently, the stochastic mathematical models of biochemical systems can be quite complex and their analysis challenging. In this paper, we present a method to reduce a stochastic continuous model of well-stirred biochemical systems, the Chemical Langevin Equation, while preserving the overall behavior of the system. Several tests of our method on models of practical interest gave excellent results.

Few‐layer carbon nitride photocatalysts for solar fuels and chemicals:Current status and prospects

Converting sunlight directly to fuels and chemicals is a great latent capacity for storing renewable energy.Due to the advantages of large surface area,short diffusion paths for electrons,and more exposed active sites,few‐layer carbon nitride(FLCN)materials present great potential for production of solar fuels and chemicals and set off a new wave of research in the last few years.Herein,the recent progress in synthesis and regulation of FLCN‐based photocatalysts,and their applications in the conversion of sunlight into fuels and chemicals,is summarized.More importantly,the regulation strategies from chemical modification to microstructure control toward the production of solar fuels and chemicals has been deeply analyzed,aiming to inspire critical thinking about the effective approaches for photocatalyst modification rather than developing new materials.At the end,the key scientific challenges and some future trend of FLCN‐based materials as advanced photocatalysts are also discussed.

Effects of Chemical Reaction on the Unsteady Free Convection Flow past an Infinite Vertical Permeable Moving Plate with Variable Temperature

Analytical solutions for the effect of chemical reaction on the unsteady free convection flow past an infinite vertical permeable moving plate with variable temperature has been studied. The plate is assumed to move with a constant velocity in the direction of fluid flow. The highly nonlinear coupled differential equations governing the boundary layer flow, heat and mass transfer are solved using two-term harmonic and non-harmonic functions. The parameters that arise in the perturbation analysis are Prandtl number (thermal diffusivity), Schmidt number (mass diffusivity), Grashof number (free convection), modified Grashof number, Chemical reaction parameter (rate constant), Skin friction coefficient and Sherwood number (wall mass transfer coefficient). The study has been compared with available exact solution in the literature and they are found to be in good agreement. It is observed that: The concentration increases during generative reaction and decreases in destructive reaction. The concentration increases with decreasing Schmidt number. The effect of increasing values of K leads to a fall in velocity profiles. The velocity decreases with increasing values of the Schmidt number. An increase in modified Grashof number leads to an increase in velocity profiles. The skin friction increases with decreasing Schmidt number. In generative reaction the skin friction decreases and in destructive reaction the skin friction increases.

Hydrogen Adsorption Study upon Ni/AI203 Nano-composite Synthesized by MOCVD Technique

The hydrogen adsorption （storage） studies upon Ni/A1203 nano-composite prepared by metal organic chemical vapor deposition technique （MOCVD） exploiting single source molec ular precursor （SSP） approach were carried out. The Ni/A1203 nano-composite is prepared in cold walled MOCVD reactor by the decomposition of SSP, [H2AI（OtBu）]2, on a substrate holding Ni（acac）2 powder. The SSP is a reducing agent which reduces Ni＋2 to Ni0 and works as source for Al203 matrix in which the Ni0 is dispersed. The resulting Ni/A1203 nano-composite is characterized by XRD, SEM, TEM, and EDX. The hydrogen adsorption （storage） studies are performed using home-made Sievert＇s type apparatus. The hydrogen storage studies reveal that approximately 2.9% （mass ratio） hydrogen can be stored in the Ni/A1203 nano-composite. The results show that Ni/A1203 nano-composite can be a po- tential candidate for hydrogen storage which can be used for onboard fuel purposes.

Study on Cultivation Techniques for Vernonia anthelmintica Willd

This article focuses on the cultivation techniques and harvesting of Vernonia anthelmintica Willd.At present,the domestic cultivation of V.anthelmintica Willd has not formed a scale,characterized with low seed yield and high harvesting cost.Therefore,it is of great significance to carry out research on the cultivation techniques and yield improvement of V.anthelmintica Willd.

Controlled Growth of Well-Aligned Carbon Nanotubes, Electrochemical Modification and Electrodeposition of Multiple Shapes of Gold Nanostructures

An efficient method has been developed to synthesize well-aligned multi-walled carbon nanotubes (MWCNTs) on a conductive Ta substrate by chemical vapour deposition (CVD). Free-standing MWCNTs arrays were functionalized through electrochemical oxidation with the formation of hydroxyl and carboxyl functional groups. Using a new oven drying technique, we demonstrate that the unidirectionally aligned and laterally spaced geometry of the CNT arrays can be retained after being subjected to each step of electrochemical modification. Samples were analyzed by using a field emission scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transformed infrared (FTIR) and Raman spectroscopy. Useful electrochemical methods for the synthesis of various gold nanostructures onto the aligned MWCNTs were then presented for the first time. The results demonstrated that flowerlike nanoparticle arrays, nanosheets and nanoflowers were obtained on the aligned CNTs under different experimental conditions. These kinds of aligned-CNT/Au nanostructures hybrid materials introduced by these efficient and simple electrochemical methods could lead to development of a new generation device for ultrasensitive catalytic and biological application.

Microscopic model for chemical etchability along radiation damage paths in solids

It would be very interesting to develop a picture about removal of atoms from the radiation damaged paths or latent nuclear tracks and undamaged bulk material in track detectors. Here, theory of chemical etching is described briefly and a new model for chemical etching along radiation damaged paths in solids is developed based on basic scientific facts and valid assumptions. Dependence of chemical etching on radiation damage intensity and etching conditions is discussed. A new parameter for etching along radiation damaged paths is introduced, which is useful for investigation of relationship between chemical etchability and radiation damage in a solid. Results and discussion presented here are also useful for further development of nuclear waste immobilization.

麝香的鉴别技术进展

麝香作为一种稀缺且具有高价值的天然香料,一直受到广泛关注。然而,市场上存在大量假冒伪劣的麝香产品,对消费者权益和产业发展造成严重影响。为了解决这一问题,持续的研究和发展麝香的鉴别技术至关重要。文章综述了当前麝香的鉴别技术进展,包括化学分析、分子生物学和同位素分析等方法。

鹿茸标准鉴别技术进展研究

鹿茸是一种具有重要药用价值的中药材,具有多种功效和广泛的临床应用。然而,由于市场上出现了大量的假冒伪劣产品,对鹿茸的鉴别技术的研究变得十分重要。本文综述了近年来鹿茸的鉴别技术进展,包括传统的鉴别方法以及现代分子生物学和化学分析技术等。同时,还对当前鹿茸鉴别技术的挑战和未来发展方向进行了讨论。