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Experimentally selecting the import prices of soybean meal raw materials from January 2017 to February 2022, spanning a total of 62 monthly periods, along with the prices of the feed industry chain as samples, this study empirically investigates the impact of soybean meal raw material import price shocks on the volatility of feed industry chain prices by constructing a VAR model. The Granger causality effect indicates that the impact of soybean meal raw material import price shocks on the volatility of feed industry chain prices has a lag effect. The impulse response suggests that when the soybean meal raw material import price experiences a positive shock of one standard deviation, the feed industry chain prices will show a 0.001 3 response starting from the second period and exhibit a sustained upward trend, reaching its peak in the 10th period. The results of the shock cycle test reveal that changes in soybean meal raw material import prices have a significantly positive impact on subsequent fluctuations in feed industry chain prices, indicating that soybean meal raw material import price shocks play a driving role in the upward movement of feed industry chain prices. Variance decomposition data results indicate that during the period of volatility in feed industry chain prices, the feed industry chain prices themselves play a dominant role, with the contribution rate showing a trend of first declining and then rising. At the same time, the impact of soybean meal raw material import price shocks on the volatility of feed industry chain prices exhibits a certain lag period, becoming evident from the third period and peaking in the 9th period, followed by a downward trend. In the paper, the recommendations are made to enhance technical support for industry cultivation, rational planning of feed planting areas, and optimization of the feed industry's supply security mechanism, providing valuable reference for stabilizing feed industry prices. [ABSTRACT FROM AUTHOR]

In recent years, the application scope of grounded theory research in the field of traditional Chinese medicine (TCM) has gradually expanded, and the various research needs such as “Dao and Shu (doctrines and techniques)” of illustrious senior TCM practitioners can be met. However, this research requires significant time and energy because of too much code, long study period and rework the meaning of code. Therefore, in this paper, on the premise of conforming to coding principles, we creatively propose a method named “ cascaded coding” that uses Office Word to code the raw materials and then imports cascaded codes into Office Excel in order to clarify all categories and the concepts at all levels attached to them. Furthermore, mind-map software is used to visualize the cascaded codes. This cascaded process is discussed in this paper, and the grounded theory is taken as an example to analyze the Dao of an illustrious senior TCM practitioner-Prof. Kong Guangyi. Based on the methodology of grounded theory coding principles, we optimize the operation path and simplify the coding process, saving time, ensuring coding efficiency and accuracy, and providing an example for researchers who conduct grounded theory research on illustrious senior TCM practitioners, thus help more TCM qualitative researchers to carry out grounded theoretical research convenienty, accurately and at low cost. [ABSTRACT FROM AUTHOR]

Protein is the main component of aquatic feed. Fish meal, as the main protein raw material, has seen a rapid increase in price in recent years. So the development of new protein ingredients has become a hot issue in aquaculture. However, the new protein ingredients contain anti-nutrition factors, which are not conducive to the digestion of aquatic animals. Therefore, it is necessary to degrade anti-nutrition factors, release nutrients, and improve the nutritional value through enzymatic hydrolysis. The paper discusses the status of enzymatic hydrolysis of different protein raw materials and their application as substitutes for fish meal in aquaculture, to provide a reference for the extensive application of enzymatic hydrolysis protein raw materials in aquatic feed. [ABSTRACT FROM AUTHOR]

Ce3+ doped gadolinium aluminum gallium garnet (GAGG:Ce) scintillation crystal has the advantages of high light output, high energy resolution, short decay time, no self radiation and non-deliquescence, which make it has a broad application prospect in nuclear medical imaging, security inspection and environment detection et al. This paper reported the Czochralski growth and scintillation properties of GAGG:Ce single crystal. GAGG:Ce raw material was synthesized by high temperature solid state reaction method. By means of XRD analysis, the raw material sintered at 1 500 °C for 12 h is verified to be pure GAGG phase. GAGG:Ce crystal with size of Φ50 mm x 90 mm was successfully grown by Czochralski method. The transmission spectrum, X-ray excited emission spectrum and pulse height spectrum of the crystal were tested. Results show that optical transmittance at 550 nm for the sample with thickness of 7 mm reaches as high as 81.5%. The X-ray excited emission peak central wavelength of the GAGG:Ce crystal is located at 550 nm. The light output of the GAGG:Ce crystal is 59 000 photons/ MeV and the energy resolution is 6.2%@662 keV. The decay time is 149 ns and a slow component of 748 ns. [ABSTRACT FROM AUTHOR]

Aquatic feed industry is one of the main factors in the development of aquaculture industry, providing strong support to meet the growing demand for aquatic products. As an important raw material in aquatic feed, lipid (especially fish oil) is easily oxidized due to its rich unsaturated fatty acids, and produces various hydroperoxides, secondary oxidation products (including alcohols, ketones, aldehydes, etc.). In addition, the oxidation process also leads to changes the oil chemical characteristics. In feed in‐ dustry and aquaculture, lipid oxidation could impair growth and health of fish. This paper summarizes the research on oil oxidation by scholars at home and abroad, discusses the effect and mechanism of oil oxidation on various kinds of fish and the application effect of common antioxidants, so as to accumulate basic data for further research on the effect of oxidized oil on aquatic animals. [ABSTRACT FROM AUTHOR]

Wood vinegar is the liquid obtained by condensation of flue gas generated during the pyrolysis of agricultural and forestry residues. Research on the preparation and application of wood vinegar can improve the utilization rate of agricultural and forestry residues and reduce environmental pollution. In this paper, the effects of pyrolysis temperature on the yield and components of wood vinegar, the effects of different raw materials and refining methods on the components of wood vinegar, the functional components, functions and application directions of wood vinegar prepared from different raw materials were comprehensively expounded by consulting a large number of literatures and materials and combining with the components determined by the authors of this paper. At the same time, the reasons for the difference in wood vinegar yield and composition were analyzed. The research progress of wood vinegar in improving soil physical and chemical indexes and biological activity, promoting crop growth, improving crop quality, controlling pests and diseases, and preparing biomass fertilizer was emphatically introduced from the aspects of different kinds, dilution concentrations, application methods, and combined application with other fertilizers. And aiming at the problems that the active ingredients are not clear in the current research process, the future research direction was presented. [ABSTRACT FROM AUTHOR]

Based on the common recipes in the official and private bibliography, this paper analyzes the hereditary characteristics of recipes. This article summarizes inheritance in three ways: complete transcription, inheritance with the same production method but slightly different textual expressions, and split inheritance. This paper briefly illustrates the main misexamples in the process of recipe literature inheritance, involving the name and content of items, processing method and time, raw material type, dosage and ratio, and food smell and taste. It will help correct the fallacies of predecessors, interpret recipe literature more correctly, and make better use of recipe literature from a practical point of view. [ABSTRACT FROM AUTHOR]

Since the industrial revolution the uncontrolled production and living activities of human society have brought about various adverse effects on the global environment among which the most urgent threat to human beings comes from climate change caused by the greenhouse effect. The Paris Agreement which marks the agreement of all countries on low-carbon transition aims to limit the global temperature increase to 2 ℃ in this century while seeking measures to further limit the temperature increase to 1. 5 ℃ and in response countries around the world are actively exploring low-carbon strategies and planning carbon reduction pathways. The goal of achieving carbon neutrality by 2060 is a requirement for all industries in China to develop corresponding carbon-neutral pathways as soon as possible. Carbon neutrality means that the carbon emissions from all activities within the selected system boundary can be offset with the carbon absorbed through natural or artificial means i. e. the carbon footprint is zero. There are photosynthetic and soil carbon sequestration activities during natural fibers' raw material acquisition stage which may be of some value to the carbon neutrality of the textile and apparel industry. However because the biochemical reactions involved in this stage are more complex compared to industrial processing operations there are still divergent opinions on the methods of accounting for its carbon footprint which brings obstacles to the evaluation of the carbon effect of natural fibers in the raw material acquisition stage and even in the whole life cycle. To grasp the progress of research on the carbon effect of natural fibers in the raw material acquisition stage and analyze the existing problems so as to help promote a more accurate and comprehensive carbon footprint accounting and carbon effect evaluation of natural fibers cotton hemp silk and wool are selected as the research objects and the current situation of carbon effect evaluation of the above four typical natural fibers in this stage is discussed by defining the scope of the raw material acquisition stage of natural fibers. The analysis of the literature shows that the research on the carbon absorption of natural fibers is insufficient compared with the research on carbon emission at the stage of raw material acquisition and the following points can be improved in subsequent related studies according to this paper i the definition of relevant terminology is not clear ii the accounting results lack comparability due to the inconsistency of the system boundary and accounting methods chosen by the existing research and the quality of production activity data is difficult to be guaranteed iii there are commonalities and differences in the growth characteristics and carbon transfer paths of various types of natural fibers at the stage of raw material acquisition and a universal theoretical model has not yet been concluded for this point iv the influence of the time factor on the results in carbon footprint accounting has not yet been agreed. In response to the above problems this paper compares the international standards and reports with high recognition in recent years and standardizes a section of terms for the study of carbon effect in the raw material stage of natural fibers then the carbon transfer pathways of two major classifications of natural fibers i. e. cellulose fibers and protein fibers are summarized in this stage which provides references for building theoretical models in addition the influence of time factors on the evaluation results of carbon effect is discussed in terms of the time boundary of the global warming potential GWP and the short-term carbon storage time of natural fiber garments. Exploring the carbon neutral path in the textile and apparel industry requires both verifying the industry's carbon emissions as well as recognizing the industry's carbon absorptions and trying to offset carbon emissions with natural carbon sinks to reduce carbon neutral costs. This paper discusses some of the problems and solution ideas for the evaluation of carbon effect at the stage of natural fiber raw material acquisition which can provide a reference for improving the carbon footprint accounting at this stage and help achieve a more comprehensive and accurate assessment of the carbon effect of natural fibers. [ABSTRACT FROM AUTHOR]

Al-Si alloy purification method is an up-and-coming method for the preparation of solar-grade polysilicon raw materials because of its low production cost, high removal efficiency and single by-product. In this process, Al as a solvent will inevitably contaminate Si, and how to reduce the content of Al in primary silicon is one of the urgent problems to be solved. In this paper, a small amount of Cu was added to Al-50%Si alloy, the effect of Cu on the thermomechanical properties of the alloy solution was analyzed, and the inhibitory effect of Cu on Al contamination in combination with the existing form of Cu was explored. The results show that the activity coefficient of Al in the alloy reduces to 0. 714 8 with 10% (mass fraction) Cu addition. The content of Al in the primary silicon reduces from 250. 960 mg/ kg to 181. 637 mg/ kg, which is 27. 62% less than that without the addition of Cu. Meanwhile, the residual Cu in primary silicon is only 12. 6 mg/ kg, which is lower than the solid solution of Cu in Si. The introduction of Cu into the Al-Si alloy does not cause secondary contamination of the primary silicon. Therefore, using Al-Si-Cu ternary alloy system for purification to prepare solar-grade polysilicon can effectively suppress Al contamination of primary silicon. [ABSTRACT FROM AUTHOR]

Transparent ceramic is a kind of inorganic nonmetallic material with broad application prospects. However, the traditional preparation strategy based on powder sintering has technical limitations of relying on high-quality raw material powder, requiring long time high temperature treatment, complex equipment and process, and high production cost. Glass crystallization is a new method to achieve full crystallization of glass and obtain transparent ceramics by controlling the crystallization process. This method can overcome the technical difficulties associated with the traditional transparent ceramic processing. Meanwhile, it also shows unique advantages in preparing high density, pore-free, non-cubic phase, nanostructured transparent ceramics and has attracted significant attention. In this paper, the development and research status of glass crystallization method were reviewed in detail from two aspects: fully glass-crystallization of oxide transparent ceramics and related component systems. Then, the problems existing in the current research were pointed out, and the future development prospects were prospected. It is expected that this method can be widely used to prepare the next generation of high performance transparent ceramic materials. [ABSTRACT FROM AUTHOR]

Black soldier fly (Hermetia illucens, BSF) is a saprovorous insect native to South America. It has the characteristics of wide diet range, rapid growth, strong reproduction ability. Due to its rich pro tein content and balanced amino acid composition, BSF is considered as a source of new aquatic feed protein sources with great potential. It has been showed that as a source of feed ingredient, BSF products can partially or even completely replace fish meal or soybean meal in aquatic animal feed, and has a good application prospect in aquaculture industry. Currently, BSF is mainly added to the aquatic feed in the form of three protein raw materials: full-fat BSF larvae meal, defatted BSF larvae meal and pre-pupa meal. Due to the different nutritional characteristics, different BSF feed products and appropriate addition level should be selected for different breeding objects to obtain the best breeding results. This paper reviewed the biological characteristics, nutritional value, factors affecting its production and the latest progress in the application of different product types of BSF protein raw material in aquatic feed, and prospected the application prospect of BSF products as protein raw materials in aquatic feed, aiming to provide reference for its industrial application. [ABSTRACT FROM AUTHOR]

The paper was to establish a method for the determination of glycyrrhizic acid in the crude extract of Codonopsis licorice as liquid feed material. The HPLC was performed on an Agilent-C18 column (4.6 mm×250 mm, 5 μm) with methanol-0.2 mol/L ammonium acetate and glacial acetic acid (67∶33∶1) as mobile phases. The column temperature was 30 ℃, the flow rate was 1.0 mL/min, and the detection wavelength was 250 nm. The results showed that the linear equation of glycyrrhizic acid was Y=7 775.2X-10.3. When the concentration of glycyrrhizic acid was in the range of 50~1 000 mg/L, the recovery was 96.09%, RSD was 1.13%. The study indicates that the method is accurate and reproducible, which is suitable for the determination of glycyrrhizic acid in the crude extract of Codonopsis licorice. [ABSTRACT FROM AUTHOR]

This paper was written based on an investigation of the statuses of rural living environments in China. By combining the main problems in rural living environments and the clean utilization of resources in China, this paper reviews and comparatively analyzes the development statuses of the clean utilization of three rural resource technologies, namely the resource utilization of rural organic waste, biomass fuel, and construction raw materials derived from organic waste. The feasibility was analyzed by considering the waste types, process paths, technical indicators, technical advantages and disadvantages, regional adaptability, and quantitative indicators. Thus, the direction of sustainable research is revealed. Furthermore, this paper proposes a specific and comprehensive technical scheme for clean resource utilization in terms of waste recycling and energy utilization in villages and towns in north and northeast China. This scheme integrates the technological utilization of multiple organic wastes fermentation, low-nitrogen combustion technology of biomass mixed materials, construction technology of active and passive village buildings, and informatization of rural living environments. It can supplement the technical scheme for improving rural living environments in north and northeast China, thereby accelerating the construction of infrastructure for such environments and laying the foundation for the synergy of living environment improvement and rural revitalization. [ABSTRACT FROM AUTHOR]

Starting from the raw materials, catalyst types and production processes, this paper reviews the domestic and foreign research progress of dodecyl mercaptan in recent decades, especially the impact on the raw materials, the advantages and disadvantages of catalysts and the production process involved in the synthesis of tert・do(lecyl mercaptan were compared and analyzed in detail・ At the same time, this paper puts forward suggestions and prospects on how to realize the localization of dodecyl mercaptan based on the development status of domestic ien-dodecyl mercaptan and upstream raw material dodecene. [ABSTRACT FROM AUTHOR]

Biochar is a kind of solid material with large specific surface area, porosity and high carbon content. In recent years, as a new type of environmental material, biochar draws the attention of the public. However, due to the influence of various factors such as raw material types and preparation technology, the effects of biochar application on soil ecosystem are complex and diverse. In this paper, the physical and chemical characteristics of biochar prepared from different raw materials were summarized, and the effects of biochar on plants, animals and microorganisms in soil ecosystem were discussed. Finally, the prospect of the research on the soil ecological effect of biochar was put forward, so as to provide the reference for the positive regulation of soil ecosystem by biochar and the rational application of biochar. [ABSTRACT FROM AUTHOR]

This paper studies the generation and emission of VOCs in the shipping industry, and analyzes the means of raw material replacement, process control and end-of-pipe treatment adopted by the shipping industry to reduce VOCs.The process principles of adsorption technology, photocatalysis technology, non-thermal plasma purification technology, catalytic combustion technology and regenerative thermal oxidizer technology in VOCs end-of-pipe treatment technology are emphatically introduced.The characteristics and applicable scope of different adsorbents and different types of adsorption processes are compared, and the advantages, shortcoming and applicable conditions of different treatment technologies are expounded.Based on the characteristics and applicable conditions of VOCs treatment technology and the current situation of VOCs treatment in the shipbuilding industry, the appropriate treatment technologies are recommended in different generation links according to VOCs emissions. Several appropriate management opinions on VOCs emission are put forward so as to provide ideas and references for the effective treatment and up to standard emission of VOCs in the shipbuilding industry. [ABSTRACT FROM AUTHOR]

This paper reviews the application of industrial sludge in the preparation of fired bricks, light aggregates, concrete materials, cement and other building materials, summarizes the current problems of industrial sludge building materials and puts forward development suggestions. Industrial sludge can be used as a substitute for clay and other raw materials to produce fired bricks, fired light aggregates and cement through sintering process, and can also be added to cement and other gel materials to prepare concrete materials, unfired lightweight aggregates and other building materials through non-burning process. Using industrial sludge to prepare building materials has great development potential. [ABSTRACT FROM AUTHOR]

With the thriving development of China's steel industry, iron tailings have become one of the most deposited industrial solid wastes in China, the treatment of which has become a key link faced by mining and smelting enterprises. With the perspective of effective utilization of iron tailings resources, the paper discussed the current research status of iron tailings in China used as concrete raw materials, sand slurry raw materials, roadbed materials, brick fabrication materials, aerated concrete materials, mine backfill materials and so on, as well as the existing problems and outlook for future development, in hope that it can provide references for the comprehensive utilization of iron tailings. [ABSTRACT FROM AUTHOR]

Sophora alopecuroides L. is a perennial herb in the leguminous family, which has the functions of clearing heat and detoxifying, antibacterial, antiviral, anti-inflammatory, analgesic, anti-tumor and insecticidal. Many researchers have developed and utilized Sophora alopecuroides L. resources by transforming different chemical components into pharmacological components and raw materials for livestock and poultry feed. In the paper, the growth characteristics, chemical composition, application value and application of Sophora alopecuroides L. in animal husbandry are reviewed, to provide reference for the development and utilization of Sophora alopecuroides L. resources. [ABSTRACT FROM AUTHOR]

In this paper, CaCl2 and KH2 PO4 were used as raw materials, Na2 EDTA·2H2 O as chelating agent, and NH3·H2 O was used to adjust pH value of the solution, the calcium-phosphate coatings on titanium substrate were prepared via hydrothermal method, and the effects of filling condition (FC) (16% ~64%) and pH value (3. 5 ~6. 0) on morphology and phase constitutions of the coatings were systematically investigated. The results show that: when the pH value is 3. 5 and 4. 0, the coatings are mainly platelet-like calcium hydrogen phosphate (DCPA) (P1) at different FC, and FC has no remarkable effect on phase constitution of the coatings; when the pH value is 4.5 and 5.0, dandelion-like hydroxyapatite (HAP) (P63 / m) are easily found at lower FC, and with the increase of FC, the coating changes from dandelion-like HAP to platelet-like DCPA; when the pH value is of 5. 5 and 6. 0, the coatings are mainly dandelion-like HAP at different FC, and with the increase of FC, the crystallinity of HAP increases, while with the increase of pH value, the diameter of dandelion-like HAP decreases. Otherwise, the wettability of the three typical coatings (i. e., the dandelion-like HAP, the platelet-like DCPA, and the mix of (HAP + DCPA)) show much better wettability than the titanium substrate, this indicates that the calciumphosphate coatings would benefit the future osseointegration. Meanwhile, the formation mechanisms of different kinds of coatings were discussed. [ABSTRACT FROM AUTHOR]

Rapeseed meal is one of the important protein raw materials because of its high protein content, but the antinutrient factors in rapeseed meal limit its application in the feed of single stomach animals. Fermented rapeseed meal can improve the nutrient apparent digestibility and palatability of rapeseed meal, thereby improving the nutritional value of rapeseed meal, and reducing the content of anti-nutrient factors that are unfavorable to growth of livestock and poultry. The paper introduces the fermentation technology of rapeseed meal, expounds the nutritional value and advantages of the fermented rapeseed meal, summarizes the feeding effect of the fermented rapeseed meal in livestock and poultry production, to provide reference for the development and utilization of rapeseed meal. [ABSTRACT FROM AUTHOR]

Seaweed is rich in resources, natural, non-toxic side effects, no residue and other characteristics, contains a variety of nutrients and bioactive substances, can improve the nutritional composition of feed, has antibacterial, antiviral, antioxidant, bonding feed and other functions, is a new source of aquatic feed raw materials and feed additives. In the paper, the nutritional composition and biological functions of seaweed powder are reviewed, and the effects of seaweed powder on promoting the growth of aquatic animals, regulating intestinal microbial composition, improving immunity, improving body color and relieving stress reaction are expounded, the application of algae powder in aquatic animal feed is prospected, to provide reference for the further application of seaweed resources in aquatic feed. [ABSTRACT FROM AUTHOR]

In this paper, carbon quantum dots was synthesized by one-step hydrothermal method using camphor leaves powder as the precursor, and a fluorescent method for Fe3+ detection was established by using it as the fluorescent probe. The results show that, at the excitation wavelength of 320 nm, the ratio of fluorescence intensity of CQDs solution after adding Fe3+ to CQDs solution without Fe3+ addition F/F0 and Fe3+ concentration shows a good linear relationship in the range of 2.72×10-5～1.00×10-4 mol/L(R²=0.9912), and the limit of detection is 8.16 μmol/L. When it is applied to the determination of iron content in iron supplements, the recovery rates of standard addition is 93.08%～105.05%. The preparation method of the carbon quantum dots is simple and fast, the raw material is environmentally friendly and easy to obtain, the method for Fe3+ detection has good linearity, high sensitivity and good selectivity, and the carbon quantum dots can be used for the analysis of iron content in actual iron supplements. [ABSTRACT FROM AUTHOR]

The 3,5-dichlorobenzoic acid has been widely used in many fields.But the traditional synthesis method is complicated and the raw materials are expensive.In this paper, with 2-nitrobenzoic acid as raw materials, a new synthetic route was designed to synthetize o-aminobenzoic acid which has an optimal ratio of yield (88.7%) under the single factor conditions.In the second step, the 2-amino-3,5-dichlorobenzoic acid was synthetized and its optimal ratio of yield can reach 84.3% via the orthogonal optimizing procedure.Lastly, the 3,5-dichlorobenzoic acid was synthetized and the response surface method was utilized to obtain an optimal yield ratio 92%.Therefore, the overall yield ratio in this route can reach more than 68%.Compared with the traditional synthesis method, this synthesis method is suitable for industrial production because the raw materials are abundant and easy to obtain; also the solvent can be recycled and reused, with less three-waste being produced. [ABSTRACT FROM AUTHOR]

As a substitute of protein, single cell protein (SCP) is a high value-added biological product. It has a good development prospect that single cell protein are transformed into animal feed products by using different organic nitrogen sources such as greenhouse gases and waste biomass and inorganic nitrogen sources in the environment. The paper reviews the production of bacteria and the production enhancement techniques, the raw materials and the application of single-cell protein in detail, to provide a reference for the application and development of SCP in the feed industry. [ABSTRACT FROM AUTHOR]

Fish meal is the main protein ingredient in commercial feed, which is also a more expensive feed ingredient. In recent years, the price of fish meal remains high, so it is very important to find low-cost and abundant vegetable protein raw materials to replace fish meal. Plant protein is an ideal substitute for fish meal in aquatic feed because of its wide source and low price. The paper reviews the sources of plant protein ingredients, the research progress of plant protein ingredients replacing fish meal, the measures to improve the utilization of plant protein ingredients, to provide reference for the efficient utilization of plant protein ingredients in aquatic feed. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore the relationship between different composting materials and their C/N ratios on nutrients and microorganisms in the composting process of kitchen waste. 【Method】In the experiment, kitchen waste, straw and sawdust were used as the main raw materials for combined composting. Through the comprehensive determination of temperature, moisture, nutrition, enzyme activity and microbial flora changes under different C/N conditions, the influence law on kitchen waste composting was summarized. 【Result】The compost with C/N ratio of 30∶1 had the best maturity effect, and the seed germination rate of each treatment reached 80%. After 100 days of maturity, each treatment met the standard of recyclable utilization, and the indicators met the industrial standard of organic fertilizer（NY525—2012）. Among them, the water content of each treatment decreased from 63% in the early stage to less than 5% in the late stage. And with the continuous composting, the pH of each treatment eventually stabilized at about 8, EC values were below 4 mS/cm, no toxic effect; The changes of total effective, available nutrients and organic matter showed a trend of rising first, reaching the peak and then gradually decreasing. The soil enzyme activities in different treatments showed a trend of first increase and then decrease, and the peak values of catalase, sucrase, urease and cellulase activities reached 5.09,9129.00,489.82,7.92 mg/（g·h）, respectively. The peak numbers of bacteria, fungi and actinomycetes in different treatments reached 23.36×108-29.45×108,1.67×108 -7.33×108,16.01×108-28.17×108 CFU/g.【Conclusion】The correlation between each index was analyzed. The compost maturity index with correlation was analyzed by principal component analysis（PCA）, and the ranking result was T6 > T4 > T5 > T1 > T2 > T3. T6 had the highest score of 1.911. The compost material was kitchen waste（2.8 t） + sawdust（0.93 t）, and the carbon-nitrogen ratio was 30∶1. Therefore, it is recommended to use kitchen waste and sawdust combined composting in production to achieve better maturity. [ABSTRACT FROM AUTHOR]

The development of low afterglow cesium iodide crystal is very important for the application of cesium iodide crystal in modern security check and medical CT equipment. In this paper, low afterglow cesium iodide crystals by co-doping were grown by an improved Bridgman method, with purified raw materials in which impurities influencing crystal afterglow were removed, the scintillation properties of the crystal were studied. The results show that the afterglow value of the crystal obtained by this method is about 0.31% @50 ms, which is much lower than that of conventional cesium iodide crystal. [ABSTRACT FROM AUTHOR]

1,4_Bis(methoxymethyl) benzene is an important fine chemical raw material and synthesis intermediate, mainly used for the synthesis of polymer resins. This paper classifies the synthetic methods of 1.4-bis (methoxy methyl) benzene and summarizes the advantages and disadvantages of these methods. The 1.4-bis(chloromethyl) benzene route has the advantages of easy availability of raw materials, simple operation and high yield, but halogens will be converted into halide salts, which results in poor atomic economy and high post-processing costs. In the 1benzenedimethanol route, when dimethyl sulfate is used as the etherificating reagent, the by-products are mainly sulfuric acid and methyl sulfate, which are strongly irritating and corrosive, requiring suitable equipment; while dimethyl carbonate is used as the etherificating reagent, the catalyst is easily available and the by-products are mainly methanol and CO2, but the reaction conditions are harsh, requiring high temperature and high pressure. Dimethyl terephthalate is directly hydrogenated to prepare 1bis(me th oxy methyl) benzene route has the simple reaction steps, but it requires expensive catalysts, high temperature and high pressure. On the whole, dimethyl carbonate used as etherificating reagent reacts with 1,4-enzenedimethanol to transesterify and decarboxylate to produce 1,4-bis (methoxymethyl) benzene, doesnJ t introduce halogens, with low contamination degree. And the release of CO2 is conducive to promoting the positive reaction, bringing high product yield. This route has the prospect of realizing green industrialized production. [ABSTRACT FROM AUTHOR]

MAX phases are a kind of new ternary layered transition metal carbonitrides, which possesses the advantages of both metal and ceramic materials. Traditional methods for synthesizing MAX phases have some limitations, such as higher temperatures, longer reaction time, few synthetic samples, and most required MAX phase can not be directly prepared by onestep. In recent years, there are more and more reports about the synthesis of MAX phases by molten salt method, and its process is continuously improved. In this paper, based on the traditional molten salt synthesis of MAX phase, the research progress of the new molten salt synthesis of MAX phase is analyzed and described. In the traditional molten salt method, the molten salt used as reaction solution with a lower melting point is used as reaction solution, thus the reaction efficiency can be improved. In molten salt shielded method, the molten salt used as reaction solution can prevent the oxidation of raw materials, so that the synthesis process can be carried out in air. Lewis acidic salt method uses molten salt as raw material to synthesize MAX phases. In the molten salts electrochemical method, the raw material changes from pure metals to metal oxides by electro deoxidation, so the cost can be reduced. In summary, the products synthesized by molten salt methods have higher yield and purity, lower reaction temperatures and costs than those synthesized by traditional methods. Therefore, the molten salt method is suitable for the large-scale syntheses of MAX phases in the future. [ABSTRACT FROM AUTHOR]

This paper mainly introduces the formation mechanism and growth mechanism of calcium sulfate whisker, expounds the raw materials, methods and application fields of the preparation of calcium sulfate whisker, analyzes the existing problems of different preparation methods, and puts forward the corresponding improvement measures. At the same time, the relationship between preparation and application is discussed, which provides scientific guidance for the future application of calcium sulfate whisker and the comprehensive recovery and utilization of resources. [ABSTRACT FROM AUTHOR]

In this paper, some regulations on the field joint coatings technology of pipeline out er anti-corrosion layer in GB/T 512•11-2017 standard and ISO 21809-3 :2016 standard are compaired and analyzed, such as the classification and material of the field joint coatings, the construction and performance index of the field joint coatings. Compared with the national standard GB/ T 512-11 - 201 7, more detailed classification for the types of field joint coatings were listed in ISO 21809-3: 2016 standard. The design temperature is relatively more meticulous for the heat-shrinkable materials in ISO 21809-:3: 2016, but the thickness of heat-shrinkable materials and the perfornrnnce requirements of raw materials are more specific in GR/ T 51241-2017. The requirements about surface treatment for heat- shrinkable materials are basically same in the two standards. In terms of the construction environment and t he;1mount of ove rlap of heat-shrinkable materials on the pipeline, the requirements are more stricter in GR/ T 51241 - 2017. ISO 2180 9-:3: 2016 adds performance indicators such as indentation resistance and lap shear strength to the performance indexes of anti - corrosive coating of heat shrinkable materials. The requirements of cathodic disbondment resistance indicators of heat shrinkable material are basically the same in two standards. [ABSTRACT FROM AUTHOR]