bluuebunny/crossref_metadata_2025_split huggingface dataset:
Technology for the production of proteolytic enzymes from the digestive organs of freshwater fish in north-west Russia
Authors: Baydalinova L S , Bazhenov E A , Grimm Th 
Published: March 2021

Abstract
This article describes the enzymatic activity of proteolytic enzymes, the general chemical composition of the digestive organs of carnivorous and herbivorous fish in the period from October to November 2017 to April 2018. The dependence of the enzymatic activity on the pH of the medium and the mass fractions of protein and fat is shown. Based on the data obtained, enzymes were isolated from the digestive organs of bream (at pH 9.5) and pike-perch (at pH 2.5). To determine the activity of the test substance, we used the corrected absorbance for the test suspension (the difference in absorbance between the test sample and the control sample) obtained using raw materials for the period January to February 2018. We also carried out the purification of enzyme preparations using ion exchangers (Q-XL, SP-XL) and size exclusion chromatography (Sephadex G-75 Superfine), determining the molecular weight of enzyme preparations prepared from the digestive organs of pike-perch and bream.
The role of bioplato in conservation of the ichthyofauna of small river ecosystems
Authors: Usov A I , Bedareva O M , Troyan T N , Sauskan V I 
Published: March 2021

Abstract
When wastewater enters water bodies, it changes both physical properties and chemical composition of water. Qualitative and quantitative composition of aquatic organisms and the biological structure of phytocenopopulations change as well. A special form of pollution is eutrophication of water bodies. The ability of photosynthetic organisms to accumulate and use substances, primarily phosphorus and nitrogen, makes them actively involved in self-purification of natural waters. The anthropogenic impact on aquatic ecosystems is increasing, therefore, monitoring and global environmental protection systems are of great relevance. The paper deals with a range of issues: the impact of gas station discharges on chemical composition of water is studied and assessed; the concentration of pollutants in water is analyzed before and after a backwater inhabited with higher aquatic plants; the effect of hydrophytes on processes of self-purification of the water body is considered. Solution of the issues made it possible to assess the impact of higher plants on chemical composition of water and self-purification processes, and biota. The impact of higher plants on concentration of pollutants in the water body was analyzed. The study revealed that higher plants reduce an adverse effect of pollutants on the biotic potential of the river ecosystem.
Immobilization of bacterial cells on nanowires
Authors: Lyachkov P O , Sidorova N A , Ya Berezina O 
Published: March 2021

Abstract
The paper investigated the effect of immobilization of bacterial cells Lactobacillus brevis 2k.Gv. on polyvinylpyrrolidone nanowires on viability and enzymatic activity of cells. The optical density of the culture solution and the growth rate of lactobacilli were measured using a Reverse-Spinner RTS-1 bioreactor to assess physiological activity of the immobilized cells. It is shown that immobilization is ‘soft’, the carrier dissolves in the culture solution after biofilm formation.
Biodegradable polymers – perspectives and applications in agriculture
Authors: Kiselev E G , Zhila N O , Volova T G 
Published: March 2021

Abstract
The paper presents a brief overview of the results of the implementation of the project “Agropreparations of the new generation: a strategy of construction and realization”. The first part contains the analysis of the growth of the wild-type strain Cupriavidus necator B-10646 (formerly eutrophus) and the synthesis of polyhydroxyalkanoates by this strain on various substrates: glycerol, palm oil, Siberian oil seed, sunflower seed oils, and oleic acid. On refined glycerin, a highly productive process is implemented when scaling up, allowing to obtain 128 ± 11 g / L PHA. Evaluation of oils has shown that palm oil is the best carbon substrate. The second part presents the results of the development of environmentally friendly slow-release pesticide formulations. They are a degradable matrix of poly-3-hydroxybutyrate mixed with natural materials (peat, clay, wood flour), into which a pesticide (metribuzin, tribenuron-methyl, fenoxaprop-P-ethyl, azoxystrobin, epoxiconazole, and tebuconazole) has been. The developed preparations showed high activity against pathogenic fungi and weeds and had a much weaker negative effect on the soil microflora. Studies of the degradation of the developed preparations and the release of pesticides into the soil confirm their effectiveness over a long period of time, up to 90 days.
Simulation of fermentolysis of secondary meat and bone raw materials
Authors: Yu Mezenova N , Naumov V A , Agafonova S V , Ya Mezenova O , Baidalinova L S , Volkov V V , Andreev M P 
Published: March 2021

Abstract
Abstarct. The study is of current relevance due to an underestimated potential of secondary meat and bone raw materials, which contain valuable bioactive substances that can be used in food, feed, cosmetic and other products. Hydrolyzing of extracting protein, fat and mineral substances from such raw materials is a promising method. The study aimed to investigate and simulate fermentolysis of highly mineralized collagen-containing raw meat with proteolytic enzymes. The experiments were carried out on beef tubular and rib bones using Alcalase 2.5 L, Protamex and Protosubtilin G3x enzymes. The efficiency of protein hydrolysis was assessed with regard to the parameters of formol titratable nitrogen, dry matter, titratable acidity, which were determined in aqueous solution of the fermentolysat. The quality indicators of the hydrolysis products were assessed by standard physicochemical methods. The data obtained were processed by methods of mathematical statistics. A mathematical model of fermentolysis of meat and bone raw materials was developed based on the analysis of graphical dependences of formol-titrated nitrogen parameters and dry matter on the enzyme preparation dosage and process duration. The models can be used to assess the decomposition level of proteins and their water extraction for various types and dosages of enzyme preparations, and to determine rational duration of fermentolysis. The model can be used as a basis to reveal the effect of the main factors on the degree of hydrolysis of proteins in meat and bone raw materials and to control the process of fermentolysis.
Environmentally friendly technology for storing organically grown apples
Authors: Nazarko M D , Kasyanov G I , Zaporozhsky A A , Kirichenko A V 
Published: March 2021

Abstract
The proposed technology is aimed at optimizing agro-ecological and biotechnological methods to guarantee safety of the harvest and quality of apple products with no toxicological effects on the environment and humans. The proposed technology for storing ecologically clean apples is improved by using a complex that implies spraying with phytopreparation and exposure to low-frequency electromagnetic field. Comparative assessment is performed for morphological, organoleptic, chemical and technological characteristics of apples, the prevalence of scab and the yield of the garden with chemical and integrated preliminary protection techniques. The effect of electromagnetic field of low frequency in the range from 18 to 100 Hz on the activity of the fruit surface microflora is evaluated. A computer program is developed and registered to be used directly for analytics and forecasting the quality of long-term storage of products.
The influence of the organo-mineral complex on the growth dynamics of the Scenedesmus quadricauda culture
Authors: Nikiforov-Nikishin D L , Kochetkov N I , Bugaev O D , Ponomarev A K 
Published: March 2021

Abstract
The paper presents data on the biotechnology of growing accumulative cultures of algae Scenedesmus quadricauda when adding organo-mineral complex drag to the culture growth medium. It is shown that the trace elements that make up the drug (trade name “Helavit”), at the studied concentrations, act in various ways stimulating and inhibiting the growth of algological culture. Having a different effect in the concentration range from 0.1 to 1 mg / L. The maximum positive effect is achieved with a drug concentration of 0.3 mg / l (8986 ± 120 103*cells/ ml), which can be recommended for mass cultivation of algae. A possible cause of inhibition of culture growth, at a concentration of 0.1 mg / l (6960 ± 115 103*cells/ ml), are the inhibitory effects of copper and iodine ions.
Results of primary screening of proteolytically active microorganisms that are promising for the transformation of organic pollution
Authors: Sidorova N A , Chechkova N A 
Published: March 2021

Abstract
In order to optimize the methods of remediation of contaminated areas, strains of microorganisms were selected that are promising for the transformation of excess amounts and the accumulation of organic matter in surface water bodies. Research has been carried out on the isolation and selection of proteolytically active strains of microorganisms from the microflora of water. Among the isolated isolates, representatives of 3 genera dominated: Pseudomonas sp., Micrococcus sp., Bacillus sp., Which differed in the rate of biomass accumulation / optical density (OD), the number of viable cells (CFU/ml) and the concentration of residual protein (mg/ml). The highest proteolytic activity was found in representatives of the genus Bacillus sp. For bacilli, within 5 days of the experiment, a 7-fold increase in biomass was observed, and the number of viable cells increased 8-fold. Due to the proteolytic activity of Bacillus sp. the concentration of the protein in the test solution decreased from 0.2412 to 0.1123 mg/ml. The research carried out opens up prospects for the creation of biopreparations of targeted action based on mono- and polycultures of proteolytics for the purposes of ecobiotechnology.
Determination of the level of comorbidity and assessment of the effect of orthopedic pathologies on basic production indicators of cattle
Authors: Gagarin E M , Glazunova L A , Tsyganok V O 
Published: March 2021

Abstract
The aim of the study was to identify the spread of hoof diseases among cattle in industrial complexes, to determine the level of comorbidity and to establish the degree of the effect of limb diseases on production and economic indicators of cattle. The studies were conducted in the period from 2018 to 2020 in two industrial complexes in the south of Tyumen region, and on the largest dairy cattle farm in Central Russia. A total of 11 602 heads of the dairy cattle were taken for clinical examination.
Orthopedic pathologies of cattle on the surveyed farms were on average widespread in 8.5% of the livestock, and hoof disease related culling of animals was 6.67±2.35%. The most common diseases are laminitis (27.0±4.38%), purulent pododermatitis (10.33±2.18%), Mortellaro disease (14.17±5.15%), interdigital dermatitis (8.37±1.15 %), and Rustergoltz ulcer (10.77±1.80%). According to the 5-point lameness scoring system proposed by D.D. Sprecher, severe cases of lameness were recorded in 10.28±0.98% of affected animals. Moderate lameness (3 points) was observed in 19.20±1.53% of animals, and weak lameness was diagnosed in 15.18±0.57% of sick animals. According to the Karl Burgi and Nigel B. Cook scale, 44.19±1.07% of cattle had a mild lesion, moderate severity was recorded in 21.88±2.78% of animals, and a severe lesion was found in 33.93±2.09% of animals. Culling of animals with musculoskeletal pathologies attained 8.48±3.04%.
Direct relationship was established between the severity of hoof lesions, the probability of comorbidity and associated pathology. It was revealed that the main indicators of production and fertility decrease due to hoof diseases, which is associated with a high level of comorbidity and accompanying gynecological diseases in addition to the main disease, delayed estrus, general decrease in the immune resistance and lack of the optimal correspondence between biological and necessary technological rhythms. The limb disease has a particular effect on fertility and reduces its level to 16% of the average fertility rate in the herd, affects manifestation of estrus (up to 48% of affected animals do not show signs of estrus), average milk production (decrease to 22 kg/day during the first lactation and to 28 kg/day during the second lactation in dairy herd with an average daily production of 32 kg/day, 38 kg/day, respectively), and the number of somatic cells in milk (increase up to 150–430 thousand units/ml).
Biotechnological potential of Lactobacillus brevis 2k.Gv for aquaculture purposes
Authors: Matrosova S V , Kuchko T Y , Sidorova N A 
Published: March 2021

Abstract
The article presents the results of a study of the biological properties of the Lactobacillus brevis 2k.Gv strain (morphological, cultural, biochemical, physiological and probiotic) in order to assess the biotechnological potential and create alternative forms of probiotics for highly productive fish farming. Under the conditions of an aquarium experiment, a positive effect of the strain on the physiological parameters of the rainbow trout Parasalmo mykiss Walbaum was found. L. brevis 2k. Gv was orally administered to fish for 30 days at a concentration of 2×108 cells/mg feed as a supplement to the main diet. It was found that the studied strain has a multifactorial effect on the fish organism. Throughout the entire period of feeding juvenile trout with extruded feed enriched with lactobacilli, no signs of infectious and somatic diseases were recorded in the experimental group of trout; hepatosomatic and splenosomatic indices of organs, as well as hematological parameters of blood remained normal. The results obtained prove the presence of probiotic properties in the Lactobacillus brevis 2k. Gv strain and the possibility of its further use as part of feed additives for therapeutic and prophylactic purposes for aquaculture objects.
Research on the damping mechanisms of composite materials
Authors: Liu Qian , Shen Yan-Jin , Wu Fangrong , Cheng Bojing 
Published: March 2021

Abstract
Traditional researches concerning the damping mechanisms of materials are limited to the phases and structures of materials, ignore the damping-related characteristics of the vibration source and of the materials themselves, and thus have great one-sidedness. This paper combines vibration science and material science on the basis of the models of mechanical vibration. Based on summarizing existing damping mechanisms, it proposes three mechanisms of damping: wave-type, particle-type and molecular force-type. By considering the macroscopic morphology of materials and the structures of molecules composing materials, it provides a guideline for preparing damping materials and studying their performance. Drawing on various research results, it also presents some inference based on available theories, creates a new perspective for researching damping mechanisms, and thus it is of high reference value for future research.
Performance Assessment of an Open Thermochemical Heat Storage (TCHS) System Using Composite Salt Hydrates
Authors: Liu H Z , Wang W T , Liu S Q , Ye Z D , Huang B J , Yu G Q , Nagano K 
Published: March 2021

Abstract
Heat storage performance of an open thermochemical heat storage (TCHS) system using composite salt hydrates of Wakkanai siliceous shale (WSS) - 9.6 wt.% LiCl was investigated numerically. A two-dimensional model considering the combined heat and mass transfer was developed. The calculation results were validated by the experimental results obtained in our previous study. The inlet air temperature, inlet air relative humidity, humid air flow rate, the ratio of the thickness of air channel and the thickness of composite solid wall, and length of the TCHS unit were evaluated to evaluate the heat storage performance. When the ratio of the thickness of air channel and the thickness of composite solid wall is 5 and the length of the heat storage unit is 0.1 m, the volumetric heat storage density of the open TCHS system can reach 510 MJ/m3.
Research on junction termination of 6500V IGBT
Authors: Gao Mingchao , Jin Rui , Wang Yaohua , Lili  , Liu Jiang , Li Cui , Sun Wanru , Nie Ruifen , Wu Junmin 
Published: March 2021

Abstract
In this paper, a novel junction termination design for 6500V IGBT is proposed. A floating P+ rings termination where the P+ rings are highly doped is less than 2500um. The termination is immune to interface charges at the Si/SiO2 interface and other layers at the top as well as in the moulding compound. The simulation results show that the breakdown voltages are all above 7000V when the interface charges change from -3E11cm−2 to 5E11cm−2. This device was fabricated and the test results show that the breakdown voltage is more than 7000V, which is agreement with the simulation results.
Multifeature pool importance fusion based GBDT (MPIF-GBDT) for short-term electricity load prediction
Authors: Lv Shengwei , Liu Gang , Bai Xue 
Published: March 2021

Abstract
Feature selection is one of the key factors in predicting. Different feature selection algorithms have their unique preferences for elemental analysis of the data. This results in failing to determine the optimal features when a dataset goes through different feature selection algorithms to get different pools of input features, which in turn affects the prediction quality. To address this problem, the method integrates and fuses the feature importance values of two different feature selection methods. Then the input feature pools are optimized and filtered for the prediction model. Finally, the multifeature pool importance fusion based GBDT (MPIF-GBDT) is developed, which integrates the different feature selection methods and predicts the short-term power load in combination with the gradient boosting decision tree algorithm. In this paper, the tree model feature selection and the Recursive Feature Elimination (RFE) are chosen as feature selection methods. The experimental results show that MPIF-GBDT can significantly improve the accuracy of the prediction compared with the benchmark model.
Sentiment analysis measure of topic mapping in LDA-LSTM combination model
Authors: Lv Yi-hang , Liu Qin , Jiang Chang-bin 
Published: March 2021

Abstract
New energy market competition incentive, how to improve the product accurately, so as to attract consumers, will become the key point for enterprises to occupy the market. From the perspective of improving products, this paper constructs a review information dimension mapping theme emotion analysis model. Firstly, LDA model is used to extract the topic of comment information. Secondly, topic mapping is carried out on the comment information to get the correlation degree between each comment information and each dimension topic. Finally, the LSTM model is constructed for sentiment analysis, and the emotional intensity of consumers in each dimension theme is measured.
Short-term wind power forecasting model based on multi-feature extraction and CNN-LSTM
Authors: Kuang Honghai , Guo Qian , Li Shengqing , Zhong Hao 
Published: March 2021

Abstract
Improving the accuracy of short-term wind power forecasting is critical to wind power consumption. This paper establishes a short-term wind power prediction model based on the multi-feature extraction and deep learning network CNN-LSTM. Muti-features are extracted from original data to improve the accuracy of training. In addition, clustering algorithm is used to classify training data and train the models corresponding to those classes. CNN-LSTM prediction models are established for each cluster and compared with ARIMA, RNN, CNN and LSTM models.
Research on Statcom Current Detection Method and Control Technology Based on Instantaneous Reactive Power Theory
Authors: Yang Linguo 
Published: March 2021

AbstractThe increase and decrease of non-linear load and impact load of power grid lead to lower and lower power quality, which has become a hot issue in reactive power compensation and harmonic suppression technology research. As one of the AC output equipments, the static synchronous compensator has strong compensation performance and can provide technical support for no power compensation. Therefore, based on the theory of instantaneous reactive power, the current detection method and related control technology of the static synchronous compensator are proposed, and finally the experimental simulation is carried out. The simulation results show that the improved detection algorithm can detect the reactive current of the system efficiently and accurately. Using STATCOM current detection method and control technology, it can adjust reactive power in time, compensate for actual power demand, further suppress system voltage fluctuations and improve system performance.
Mechanical and electronic properties of 2D black phosphorene nanoribbons: A first-principles study
Authors: Miao Yufei , He Luwu 
Published: March 2021

Abstract
The mechanical and electronic properties of black phosphorene nanoribbons are studied using the first-principles calculations. The armchair black phosphorene nanoribbons (APNR) are obtained and the atomic reconstruction is found at the edge of the nanoribbons. In addition, the strain field is applied on the nanoribbons, and its stress-strain curve, Young’s modulus, and Poisson’s ratio are calculating by stretching APNR. It is found that the Young’s modulus enhanced with the increase of nanoribbons width. It is significantly lower than the Young’s modulus of monolayer black phosphorene. On the contrary, the Poisson’s ratio hardly changes with the increase of nanoribbons width. Finally, it is found that the band gap of APNR decreases with the increase of nanoribbons width and increases monotonically with the increase of strain.
Simulation and optimization of NO generation characteristics of ultra supercritical compact boiler
Authors: Dai Wentai , Liu Jianquan , Zhong Li 
Published: March 2021

Abstract
Computational fluid dynamics numerical simulation method was used to numerically simulate the combustion process in 700 °C ultra-supercritical compact swirl opposed coal-fired boiler. The flow field distribution, composition distribution and NO distribution in the furnace were obtained through simulation. Simulating the NO generation in the boiler when the burner is put into different operation modes under different loads. The results show that the velocity and temperature fields in the ultra-supercritical compact boiler have the same characteristics as the typical swirl opposed coal-fired boiler. The O2 concentration showed good consistency with the main gas products CO and CO2 concentration. To a certain extent, NO generation and distribution characteristics are related with the temperature field. When the burner is put into operation in different ways, NO generation and distribution are different correspondingly. The simulation and test can provide theoretical basis for the technical implementation and structural optimization of the ultra-supercritical compact boiler at 700 °C.