Gentiana macrophylla Pall.:a review of the basic source,traditional use,chemical components,pharmacological activities and quality control

Gentiana macrophylla Pall.(G.macrophylla),whose genus and family belong to the Gentianaceae and Gentiana.The main distribution centers of G.macrophylla resources were the Loess Plateau and the eastern Qinghai-Tibet Plateau in China.G.macrophylla,as a traditional medicine,has a long history and was used in different ethnic medicines.Its roots were used in traditional Chinese medicine,which had the effect of anti-inflammatory,anti-rheumatism,antiviral,promote blood circulation,eliminate swelling and pain,while its flowers were used in traditional Mongolian medicine,which had the effect of removing“Xieriwusu”(“Xieriwusu”means rheumatism),antiviral,reducing swelling.From previous studies,it could be found that there were more than forty components isolated and identified from G.macrophylla.The main chemical components were iridoids,flavonoids,triterpenoids,steroids,phenylpropanoids,and alkaloids.Iridoid terpenoid components represented by gentiopicroside and Loganic acid were the main components of the root of G.macrophylla,which had anti-inflammatory,antioxidant,hepatoprotective,analgesic,antibacterial and promote gastrointestinal tract activities.The flower mainly contains isoorientin and isovitexin as the representative of flavonoids.They have anti-tumor,liver protection,heart protection,inhibition of acetylcholinesterase and inhibition of melanin.It could be seen from previous studies that the research on G.macrophylla was mainly focused on the root,and the flower was rarely studied.It was reported that the experimental data of the anti-inflammatory and anti-tumor effects of G.macrophylla flowers show that its curative effect was very good.Therefore,the flowers of the flower of G.macrophylla can be used as potential medicinal parts for research.Given that flavonoids are mostly found in flowers and exhibit a range of functions,it is possible to investigate the flowers in order to learn more about G.macrophylla’s potential medical benefits.Based on botanical books,Chinese classic texts,medical monographs and academic search engines(Google,Google Scholar,Web of Science,SciFinder,Pubmed,CNKI,Sci-hub,Elsevier and Wanfang),the data and information on G.macrophylla in the past 20 years are inquired and summarized comprehensively.The basic source,traditional use,chemical composition,biological activity,pharmacodynamics and quality control of G.macrophylla was systematically reviewed,in order to provide reliable basis for the subsequent development and utilization of G.macrophylla.

Chemical simulation teaching system based on virtual reality and gesture interaction

Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based on virtual reality and gesture interaction.Methods The parameters of the models were obtained through actual investigation,whereby Blender and 3DS MAX were used to model and import these parameters into a physics engine.By establishing an interface for the physics engine,gesture interaction hardware,and virtual reality(VR)helmet,a highly realistic chemical experiment environment was created.Using code script logic,particle systems,as well as other systems,chemical phenomena were simulated.Furthermore,we created an online teaching platform using streaming media and databases to address the problems of distance teaching.Results The proposed system was evaluated against two mainstream products in the market.In the experiments,the proposed system outperformed the other products in terms of fidelity and practicality.Conclusions The proposed system which offers realistic simulations and practicability,can help improve the high school chemistry experimental education.

Chemical Control of Herbicide Monosulfuron Plus Propazine 44% WP against Weeds in Millet Fields and Study on Factors Influencing Yield of Millet

[Objective] The paper was to resolve the poor efficacy or phytotoxicity problems in promotion of herbicide monosulfuron plus propazine 44% WP. [Method] Using orthogonal test and Duncan＇s new multiple range statistical analysis with four factors four levels and three factors two levels, the effects of factors such as herbi- cide dose, irrigation water volume, quality of soil preparation and soil moisture content on chemical control of monosulfuron plus propazine 44% WP against weeds and millet yield were compared in the test. [Result] Seven factors all had great impact on control effect of monosulfuron plus propazine 44% WP against weeds, of which her- bicide dose, irrigation water volume, quality of soil preparation and soil moisture content were the most important factors affecting millet yield. According to millet yield and economic benefit, the optimal scheme to ensure safe, efficient and economic control of monosulfuron plus propazine 44% WP against weeds was as follows： the dose of monosulfuron plus propazine 44% WP was 1 800 g/hm2, the soil was treat- ed after sowing and before seedling emergence; the soil should be smooth and sol- id; the soil moisture should reach 15%; the fields should not be irrigated after herbi- cide application, and the damage of weeds in millet fields could be effectively con- trolled within 45 d during high efficacy duration, especially the damage of dicotyledonous weeds. [Conclusion] The study provided useful information for comprehensive technology of weeds control and ensuring high yield and good harvest of millet.

Multivariable Decoupling Predictive Control with Input Constraints and Its Application on Chemical Process

A constrained decoupling (generalized predictive control) GPC algorithm is proposed for MIMO (malti-input multi-output) system. This algorithm takes account of all constraints of inputs and their increments. By solving matrix equations, the multi-step predictive decoupling controllers are realized. This algorithm need not solve Diophantine functions, and weakens the cross-coupling of the variables. At last the simulation results demon- strate the effectiveness of this proposed strategy.

Novel Control Vector Parameterization Method with Differential Evolution Algorithm and Its Application in Dynamic Optimization of Chemical Processes

Two general approaches are adopted in solving dynamic optimization problems in chemical processes, namely, the analytical and numerical methods. The numerical method, which is based on heuristic algorithms, has been widely used. An approach that combines differential evolution （DE） algorithm and control vector parameteri- zation （CVP） is proposed in this paper. In the proposed CVP, control variables are approximated with polynomials based on state variables and time in the entire time interval. Region reduction strategy is used in DE to reduce the width of the search region, which improves the computing efficiency. The results of the case studies demonstrate the feasibility and efficiency of the oroposed methods.

Design and control of chemical compositions for high-performance austempered ductile iron

This paper presents the effects of chemical compositions of austempered ductile iron （ADI） on casting quality, heat treatment process parameters and mechanical properties of final products. Through experiment and production practice, the impacts of carbon equivalent on ADI and its mechanical properties have been studied. Proper content ranges for carbon and silicon have been obtained to avoid ADI casting shrinkage and graphite fioatation, as well as to achieve the optimal mechanical properties. According to the impact of silicon content on austenite phase transformation, the existing form of carbon in ADI has been analyzed, and also the formula and diagram showing the relationship between austenitizing temperature and carbon content in austenite have been deduced. The chemical composition range for high performance ADI and its control points have been recommended, to serve as a reference for production process.

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.

A New Optimal Control System Design for Chemical Processes

Based on frequency response and convex optimization,a novel optimal control system was developed for chemical processes.The feedforward control is designed to improve the tracking performance of closed loop chemical systems.The parametric model is not required because the system directly utilizes the frequency response of the loop transfer function,which can be measured accurately.In particular,the extremal values of magnitude and phase can be solved according to constrained quadratic programming optimizer and convex optimization.Simulation examples show the effectiveness of the method.The design method is simple and easily adopted in chemical industry.

EXPERT SYSTEM FOR SINTER CHEMICAL COMPOSITION CONTROL BASED ON ADAPTIVE PREDICTION

In order to stabilize the sinter chemical composition,the expert system for composition control based on adaptive prediction has been developed on the basis of modern control theory and artificial intelligence.It has been verified by using real data at No.3 Sintering Plant of Anshan Iron and Steel Co.,and satisfactory results have been obtained.

Nonlinear incidence rate of a pest management SI model with biological and chemical control concern

A pest management SI model with impulsive releases of infective pests and spraying pesticides is proposed and investigated. We prove that all solutions of the model are uniformly ultimately bounded. We also obtain the sufficient conditions of globally asymptotic stability periodic solution of pest-extinction and permanence of the model. The approach of combining impulsive releasing infective pests with impulsive spraying pesticides provides reliable tactical basis for the practical pest management.

Effects of chemical ecological adjustment and control experiment on phytoplankton community in the Aoshan Bay

There is a low nutrient level in the Aoshan Bay. In June 1999, the chemical adjustmentand control experiment was made in the Aoshan Bay. Following tracts investigation was carried out before the experiment and on the 1st, 2nd, 4th, 5th, 6th and 45th day/after the experiment. While the variance of amount of phytoplankton, the replacement of superior species and the species composition of phytoplankton were researched. The results show that the amount of phytoplankton in the Aoshan Bay rises gradually after the experiment. Ceratium macroceros Cleve of pyrophyta was the dominant species before the experiment, its dominant index was 37.7%. Six days after the experiment, its dominant index dropped to 17.6% . Meanwhile the dominant index of Asterionella japonics Cleve rose from 7.1% to 39.2% , it became the first dominant species. Forty-five days after the experiment, the amount of phytoplankton in the Aoshan Bay was 5.15 to 137.32 times more than that in 1997.

Weed Occurrence and Chemical Control Test in Public Lawn of Suzhou Urban Area of China

Weed occurrence and damage in public green lawn of Suzhou urban area was assessed using five-grade weed visual survey method. The occurrence and damage of weeds in public green lawn of Suzhou City was very common. There were totally 67 species of weeds in green lawn, with the density of 6.5 plant/m^2, the relative abundance of 7.6%, the relative coverage of 10.3%, the relative height and the occurrence frequency of 100%, and the overall damage level of weeds was above the forth level. There were 14 species of major weeds causing damage, and 15 species of weeds were found to pose regional damage. Haloxyfop-R-methyl or Ping＇an-14 could be applied to control grassy weeds in clover lawns, with the herbicidal effect above 90%. MCPA, fluroxypyr, or clopyralid could be administra- ted alone to control broadleaf weeds in Cynodon dactylon or Festuca elata lawn, with the herbicidal effect above 85%. Since the weed species in weed communities of lawn were different, the types of herbicides should be targeted, or SD additives could be added to improve the herbicidal effect.

Effects of Straw Returning and Chemical Control on Occurrence Quantity of Athetis lepigone Moschler in Summer Maize Fields

Athetis lepigone Moschler is a new kind of insect pest occurring in summer corn production areas. By investigation, it was found especially serious in straw returning fields. In this paper, its damage status was investigated in straw returning and chemical controlled fields, respectively. The results showed that the rate of damaged plants was 82% and the maximum pest number per 100 plants was 88 heads in the straw returning fields without chemical control. The application of herbicides and pesticides had no significant effects on occurrence quantity and damage rate, but the pest number per 100 plants decreased a little compared to the fields without chemical control. In the surer er maize fields without straw returning, the application of herbicides and pesticides could significantly decrease the damage of Athetis lepigone, the rate of damaged plants was 20%, and the pest number per 100 plants was 6.

Controllable growth of wafer-scale PdS and PdS_(2) nanofilms via chemical vapor deposition combined with an electron beam evaporation technique

Palladium(Pd)-based sulfides have triggered extensive interest due to their unique properties and potential applications in the fields of electronics and optoelectronics.However,the synthesis of large-scale uniform PdS and PdS_(2)nanofilms(NFs)remains an enormous challenge.In this work,2-inch wafer-scale PdS and PdS_(2) NFs with excellent stability can be controllably prepared via chemical vapor deposition combined with electron beam evaporation technique.The thickness of the pre-deposited Pd film and the sulfurization temperature are critical for the precise synthesis of PdS and PdS_(2) NFs.A corresponding growth mechanism has been proposed based on our experimental results and Gibbs free energy calculations.The electrical transport properties of PdS and PdS_(2) NFs were explored by conductive atomic force microscopy.Our findings have achieved the controllable growth of PdS and PdS_(2) NFs,which may provide a pathway to facilitate PdS and PdS_(2) based applications for next-generation high performance optoelectronic devices.

Evaluation of Selected Chemical,Biological Fungicides,and Induced Resistance to Control White Rot(Sclerotium rolfsii Sacc.)on Tomato

Tomato(Solanum lycopersicum)is one of the most widely grown and consumed as fresh vegetable in the world.Sclerotium rolfsii Sacc.is one of the most destructive diseases and affects more than 500 plant species.This study was conducted for“Evaluation of Selected Chemical,Biological Fungicides,and Induced Resistant to Control White Rot(Sclerotium rolfsii Sacc.)on Tomato”.The experiment was conducted at the Royal University of Agriculture and divided into two sections.The first section conducted under in vitro condition consists of four treatments T1 control treatment,T2 copper hydroxide,T3 azoxystrobin+difenoconazole,T4 metalaxyl+mancozeb in Nagoya Laboratory,and had been starting from 11st May to 15th May 2020.Section two was conducted in a pot in net-house which started from 1st January 2019 to 19th February 2019 and 1st January to 19th February 2020 and arranged in RCBD(Randomized Completely Block Design)with six replications and nine treatments.T0 negative control,T1 inoculate but not treatment,T2 metalaxyl+mancozeb,T3 azoxystrobin+difenoconazole,T4 copper hydroxide,T5 acibenzolar-S-methyl,T6 chicken dung+Trichoderma harzianum,T7 acibenzolar-S-methyl+chicken dung+Trichoderma harzianum,T8 acibenzolar-S-methyl+metalaxyl+mancozeb.Data were collected on colonizing diameter in vitro.For pot experiment collected on disease incidence,incubation period Based on the result under in vitro condition metalaxyl+mancozeb highly inhibited germination of Sclerotium rolfsii when compared with another treatment.However,the application of copper hydroxide seems less effective compared with control.For in pot experiment,when treated after symptom of southern blight appeared to seem less effective on the severity of southern blight.In contrast,when applied as a protectant and curative when symptoms appeared only systemic fungicide azoxystrobin+difenoconazole significantly reduced the severity of Sclerotium rolfsii and delayed incubation period while compared with other treatments(p<0.05)and was followed by metalaxyl+mancozeb,whereas,copper hydroxide,acibenzolar-S-methyl,chicken dung+Trichoderma harzianum,acibenzolar-S-methyl+chicken dung+Trichoderma harzianum,acibenzolar-S-methyl+metalaxyl+mancozeb were less effective(p>0.05).Based on the three experiments we can assume that fungicide is more effective in reducing the growth of the pathogen and delaying the incubation period of fungal colonization when compared with biological control and induced resistance.

Effects of Torreya grandis Root Rot on Seedling Growth and Screening of Its Chemical Control Agents

[Objectives]This study was conducted to prevent the occurrence of root rot disease in Torreya grandis and improve the yield and quality of T.grandis.[Methods]One-year-old and two-year-old seedlings of Torreya grandis‘Xifei’and‘Cufei’were inoculated with the root rot pathogen Fusarium fujikuroi,and the changes in photosynthesis,chlorophyll content,malondialdehyde,and defense enzyme system(superoxide dismutase,peroxidase,and catalase)activity in leaves of T.grandis seedlings were investigated using water as a control.Meanwhile,the control effects of 80%carbendazim wettable powder,64%metalaxyl·mancozeb wettable powder,430 g/L tebuconazole suspension and 30%difenoconazole·cyproconazole EC on root rot in T.grandis were investigated.[Results]After inoculation with the pathogen F.fujikuroi,the net photosynthetic rates and transpiration rates in leaves of T.grandis‘Xifei’and‘Cufei’decreased,and the contents of chlorophyll decreased,while the contents of malondialdehyde increased,and the contents of superoxide dismutase and catalase increased with time.However,peroxidase showed a high activity in T.grandis‘Cufei’only,but a trend of"increasing-decreasing-increasing"in T.grandis‘Xifei’.Among the four chemical control agents,64%metalaxyl·mancozeb wettable powder had the best control effect on root rot of T.grandis caused by the pathogenic fungus F.fujikuroi.[Conclusions]The net photosynthetic rate,transpiration rate,chlorophyll content,malondialdehyde content,superoxide dismutase activity and catalase activity could all be used as screening indicators for T.grandis varieties resistant to root rot.Meanwhile,64%metalaxyl·mancozeb wettable powder could be used as a control agent for root rot on T.grandis.

Research on Chemical Prevention and Control against Stem Base Rot of Sweet Potato

[Objective]The paper was to effectively control stem base rot of sweet potato.[Method]Chemical prevention and control test against stem base rot of sweet potato were conducted for consecutive three years from 2016 to 2018.[Result]The use of carbendazim or carbendazim+mancozeb,and carbendazim+embamycin had significant control effect on stem base rot of sweet potato.However,the applied concentration should be higher than the recommended concentration.Especially the concentration of 50%carbendazim WP should be no more than 300 times,and the prevention and control effect of 100 times dilution would be better.[Conclusion]The types and concentrations of prevention and control agents are determined in the test,which will provide certain basis for chemical prevention and control against stem base rot of sweet potato.

Biological and Chemical Control in Rot Root in Avocado by Phytophthora cinnamomi Rands

＂Avocado sadness＂ caused by the Oomycete Phytophthora cinnamomi Rands, is one of the main diseases affecting this fruit crop in Michoacan, M6xico, without having an efficient control strategy for that. In this research three Trichoderma isolates and Ridomil Gold 4E fungicide were tested in avocado trees infected with this pathogen using the growing and coloring vegetative flow growing. Results were analyzed with an experimental design completely random with four treatments and repetitions. Different responses were presented form avocado trees to each treatment. Trichoderma erinaceum Bissett, Kubicek ＆ Szackacs treatment was the best controlling disease in trees with grade II and III damage. Trichoderma aggressivum Samuels ＆ W. Gams controlled better in trees with grade III damage. At last, Trichoderma arundinaceum Zafari, Graef. and Samuels were the best controlling trees with the highest grade damage. Fungicide Ridomil Gold 4E controlled the disease in trees with the lowest grade damage （I and II）, their medias were similar to witness.

Study on the Effective Prevention and Control of Maize Rough Dwarf Disease in Different Areas with Varying Epidemic Intensity in Shandong Province

[ Objective] This study aimed to investigate the effective prevention and control of maize rough dwarf disease in different areas with varying epidemic inten-sity in Shandong Province. [Method] Control effects of single application of virus in-hibitors and composite application of virus inhibitors with seed dressing agents and pesticides on maize rough dwarf disease in different areas with varying epidemic intensity were investigated. [Result] The same treatment possessed entirely different effects in severely affected areas and slightly affected areas. To be specific, single application of virus inhibitors in slightly affected areas exhibited good control effects, with a control efficiency of 76.59% and yield increment rate of 158.21%; in severely affected areas, single application of virus inhibitors led to low control efficiency and yield increment rate. The highest control efficiency of composite application of virus inhibitors with seed dressing agents and pesticides in severely affected areas was 71.38%, and experimental plots changed from total crop failure to have certain eco-nomic output. [Conclusion] ln different areas with varying epidemic intensity of maize rough dwarf disease, different application modes should be adopted according to lo-cal conditions, thereby saving cost and improving control efficiency.