Online identification and extraction method of regional large-scale adjustable load-aggregation characteristics

This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online identification method is a computer-involved approach for data collection,processing,and system identification,commonly used for adaptive control and prediction.This paper proposes a method for dynamically aggregating large-scale adjustable loads to support high proportions of new energy integration,aiming to study the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction methods.The experiment selected 300 central air conditioners as the research subject and analyzed their regulation characteristics,economic efficiency,and comfort.The experimental results show that as the adjustment time of the air conditioner increases from 5 minutes to 35 minutes,the stable adjustment quantity during the adjustment period decreases from 28.46 to 3.57,indicating that air conditioning loads can be controlled over a long period and have better adjustment effects in the short term.Overall,the experimental results of this paper demonstrate that analyzing the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction algorithms is effective.

Comparison of RNA Extraction Methods of Sugarcane Stem

[Objective] The study was to explore the most effective and feasible method for sugarcane stalks RNA extraction.[Method] SDS extraction method,kit extraction method and GHCL extraction method were used to extract the sugarcane RNA in stalks,and the quality of the extracted RNA was compared.[Result] RNA extracted by kit extraction method had a high-yield,the bands were clear and RNA had a good integrity,there was no significant degradation of RNA,and the OD260 nm/OD280 nm value was closed to 2.0.[Conclusion] Kit extraction method was the effectively method to extract sugarcane RNA,and this study had provided a theoretical basis for the molecular biology study of sugarcane.

Comparison of Genomic DNA Extraction Methods for Chenopodium quinoa Willd

To rapidly obtain high-quality genomic DNA from Chenopodium quinoa Willd, the genomic DAN in different tissues （leaves, stems and roots） of Chenopodi- um quinoa Willd was extracted by modified CTAB method, SDS method and high- salt Iow-pH method, respectively. The quality and yield of extracted DNA was deter- mined using agarose gel electrophoresis and UV spectrophotometry. At the same time, the PCR-SSR and SSCP molecular detection was also performed. The results showed that the gel test strips, without obvious decomposition, of all the extraction methods were relatively obvious; the genomic DNA yield extracted by modified CTAB method was highest, followed by that by SDS method, and the genomic DNA extracted by high-salt Iow-pH method was lowest： the genomic DNA yields extracted by different methods from Chenopodium quinoa Wiltd leaves were all high- er than those from roots and stems; the quality of Chenopodium quinoa Willd ge- nomic DNA extracted by modified CTAB method and high-salt Iow-pH method was better, and polyphenols, polysaccharides and other impurities were removed more completely. The PCR-SSR and SSCP detection results showed that the genomic DNA extracted by different methods from different tissues of Chenopodium quinoa Willd all could be better amplified, and high-quality strips could be obtained. So the Chenopodium quinoa Willd genomic DNA extracted by the three methods all can be used for subsequent molecular biology research.

Isolation of Chlorella vulgaris and Its DNA Extraction Methods

[Objective] The aim of this study is to isolate Chlorella vulgaris(chlorella)and extract its genomic DNA.[Method] Both the dilution method and drip method were employed to isolate chlorella from lake water samples;the conditions for culturing chlorella were optimized and its genomic DNA was extracted by improved CTAB method and SDS method.[Result] The proper conditions for chlorella culture were as following:temperature 20-25 ℃,illumination 4.39-5.86 W/m2 and rotational speed 100-150r/min;improved CTAB method was suitable for extracting genomic DNA from chlorella.[Conclusion] The study is helpful to study the chlorella at molecular level and promote the exploitation and utilization of chlorella resources.

Comparison on Four Extraction Methods of Genomic DNA from Clematis fasciculiflora Franch

[Objective] This study aimed at comparing the four extraction methods of genomic DNA from Clematis fasciculiflora Franch and determining the optimal extraction method for extracting the genomic DNA from Clematis fasciculiflora Franch.[Method] Leavies of Clematis fasciculiflora Franch were used as materials for comparing the purity and concentration of extracted DNA and extracting time among the four extraction methods of genomic DNA including improved CTAB method Ⅰ,improved CTAB method Ⅱ,improved CTAB method Ⅲ and improved SDS method.[Result] The four extraction methods could all be successfully used for extracting the genomic DNA from Clematis fasciculiflora Franch.The purity of genomic DNA was the highest using improved CTAB method Ⅰ,with the longest extracting time;while the concentration of genomic DNA was the maximum using the improved SDS method,with the shortest extracting time and relatively low purity;the extracting time of improved CTAB method Ⅲ was the shortest.[Conclusion] This study had established the optimal extraction method for extracting the genomic DNA from Clematis fasciculiflora Franch and supported for the further research using molecular biological methods.

HPLC Determination of the Major Non-protein Amino Acids and Common Biogenic Amines in Lathyrus sativus Using a Novel Extraction Method

An assay is presented for simultaneously determining 5 biogenic amines and the major non-protein amino acids: the toxin β-N-oxalyl-L-α,β-diaminopropanoic acid (β-ODAP), its isomer α-ODAP and homoarginine in Lathyrus sativus extracts using the HPLC system after derivatization with para-nitrobenzyloxycarbonyl chloride (PNZ-Cl). However, it is more worthy of noting that this paper also describes a new extraction method using 0.2 mol/L HClO4. The new method has some advantages: shorter extraction-time, simultaneous extraction of free amino acids and polyamines, better inhibiting the isomerization of β-ODAP to α-ODAP, and so on.

Effects of dietary oil sources and fat extraction methods on apparent and standardized ileal digestibility of fat and fatty acids in growing pigs

Background:There is a lack of data for the standardized ileal digestibility(SID) of fat and fatty acids in national feed databases.In addition,it is important to specify the procedures used for fat analyses.Therefore,an experiment was conducted to 1) determine the apparent ileal digestibility(AID) and SID of fat and fatty acids in ten different oil sources for growing pigs and to develop prediction equations for SID of fat based on fatty acid composition;and 2) compare the effect of the fat extraction methods on the calculated values for endogenous loss and digestibility of fat.Methods:Twenty-two barrows(initial body weight:32.1 ± 2.3 kg) were surgically fitted with a T-cannula in the distal ileum,and allotted to 1 of 11 experimental diets in a 4-period Youden Square design.A fat-free diet was formulated using cornstarch,soy protein isolate and sucrose.Ten oil-added diets were formulated by adding 6% of dietary oil sources to the fat-free diet at the expense of cornstarch.All diets contained 26% sugar beet pulp and 0.40% chromic oxide.Results:The endogenous loss of ether extract(EE) was lower than that of acid-hydrolyzed fat(AEE;P < 0.01).There were significant differences in the AID and SID of fat and saturated fatty acids across the dietary oil sources(P < 0.05).The SID of AEE for palm oil was lower than that of sunflower oil,corn oil,canola oil,rice oil and flaxseed oil(P < 0.01).The AID and SID of fat ranged from 79.65% to 86.97% and from 91.14% to 99.18%.Although the AID of EE was greater than that of AEE(P < 0.01),there was no significant difference in SID of EE and AEE except for palm oil.The ratio of unsaturated to saturated fatty acids(U/S) had a positive correlation with SID of fat(P < 0.05),whereas C16:0 and long chain saturated fatty acids(LSFA) were significant negatively correlated with SID of fat(P < 0.01).The best-fit equation to predict SID of fat was SID AEE = 102.75-0.15 × LSFA-0.74 × C18:0-0.03 × C18:1(Adjusted coefficient of determination = 0.88,P < 0.01).Conclusions:When calculating the SID of fat,the EE content of the samples can be analyzed using the direct extraction method,whereas the acid hydrolysis procedure should be used to determine the AID of fat.Fat digestibility of dietary oils was affected by their fatty acid composition,especially by the contents of C16:0,LSFA and U/S.

Performance comparison of different microbial DNA extraction methods on bird feces

Background:As an important player during food digestion,gut microbiota has attracted much attention in diet adaptation studies in birds.Microbiota extracted from feces has been widely used as a proxy for gut microbiota.Although several methods have been developed for microbial DNA extraction,their performances in the bird feces have not been systematacially evaluated yet.Methods:In this study,we applied three DNA extraction methods(Qiagen,MoBio and Bead)to extract DNA from feces of three avian dietary guilds(granivore,omnivore and carnivore),sequenced V4 region of 16S rRNA gene for each extract and evaluated the performances of DNA yield,DNA integrity,microbial composition,cell lysis capacity and alpha diversity for the three methods on each dietary guild.Results:Bead method was the best on the performance of both DNA yield and DNA integrity regardless of dietary guild.In granivore,microbial relative abundance at both species and phylum levels,alpha diversity and cell lysis capacity were comparable among all methods.In omnivore,Qiagen had the best performance on alpha diversity,fol-lowed by Bead and MoBio.There were small variations on microbial relative abundance at both species and phylum levels among different extraction methods.MoBio exhibited the best performance on cell lysis capacity.In carnivore,considerable variations were found on microbial relative abundance at both species and phylum levels.Qiagen had the best performance on alpha diversity,followed by MoBio and Bead.MoBio had the highest cell lysis capacity.Conclusions:DNA yield and integrity have no obvious impact on microbial composition,alpha diversity or cell lysis capacity.The microbiota results(e.g.,microbial composition,cell lysis capacity,alpha diversity)obtained from differ-ent methods are comparable in granivorous avian species but not in omnivorous or carnivorous birds.Either method could be used in granivore microbiota studies.For omnivores and carnivores,we recommend Qiagen method when the research purpose is microbial diversity and MoBio when gram-positive bacteria is the research target.

Study on Extraction of Effective Aroma Components from Formula Tobacco by the Supercritical CO2 Extraction Method and Its Aroma Composition

[Objectives]This study was conducted to improve the sensory quality and industrial availability of tobacco extracts.[Methods]The L9(34)design was adopted to carried out an extraction experiment,in which formula tobacco was extracted using supercritical CO2,and the extract was concentrated by vacuum distillation.Through sensory evaluation and chemical analysis,the function determination and chemical composition analysis of the tobacco extracts were carried out,and the optimal supercritical fluid extraction process was finally determined.[Results]The obtained optimal supercritical fluid extraction conditions were as follows:extraction temperature 55℃,extraction pressure 25 MPa,CO2 flow rate of 20 L/h,and entrainer of 95%ethanol.The tobacco extract obtained under the optimal conditions endowed the cigarettes with full and delicate aroma,less irritation and clean aftertaste and made the flavor of the cigarettes overall coordinated and softer,so the sensory quality was significantly improved.[Conclusions]The tobacco extract obtained by the supercritical CO2 extraction method from formula tobacco can effectively improve the quality of cigarettes.

Evaluation Indicators and Extraction Method for Pitting Corrosion of Structural Steel

A set of evaluation indicators based on corrosion ratio in theory for assessing the extent of pitting corrosion and performance reduction are proposed. In order to quantify the morphology of pitting corrosion and extract the evaluation indicators,the 3D profile data obtained by pitting morphology measurement are imported into a special written program to automatically determine the location of each corrosion pit and distill any desired data pertinent to the pitting morphology. The results show that this method seems to be effective to analyze the corroded surface and characterize the pitting morphology.

Advances in Studies on Extraction Methods and Physiological Activities of Jujube Flavonoids

Jujube is rich in nutrients and functional active ingredients. For example,jujube flavonoids have significant anti-oxidation,anticancer,antibacterial and anti-inflammatory functions. This paper elaborated the advances in the studies about the extraction methods,purification methods,antioxidant properties,stability and antibacterial effects of jujube flavonoids,in order to provide a certain reference for the study of jujube flavonoids.

A multi-criteria decision-making approach for comparing sample preservation and DNA extraction methods from swine feces

Molecular microbiological methods, such as competetive PCR, real-time PCR, denaturing gradient gel electrophoresis (DGGE) and large-scale parallel-pyrosequencing, require the extraction of sufficient quantity of high quality DNA from microbiologically and chemically complex matrices. Due to difficulties in the field to standardize/select the optimum DNA preservation-extraction methods in view of laboratories differences, this article attempts to present a straight-forward mathematical framework for comparing some of the most commonly used methods. To this end, as a case study, the problem of selecting an optimum sample preservation-DNA extraction strategy for obtaining total bacterial DNA from swine feces was considered. Two sample preservation methods (liquid nitrogen and RNAlater?) and seven extraction techniques were paired and compared under six quantitative DNA analysis criteria: yield of extraction, purity of extracted DNA (A260/280 and A 260/230 ratios), duration of extraction, degradation degree of DNA, and cost. From a practical point of view, it is unlikely that a single sample preservation-DNA extraction strategy can be optimum for all selected criteria. Hence, a systematic multi-criteria decision-making (MCDM) approach was used to compare the methods. As a result, the ZR Fecal DNA MiniPrepTM DNA extraction kit for samples preserved either with liquid nitrogen or RNAlater? were identified as potential optimum solutions for obtaining total bacterial DNA from swine feces. Considering the need for practicality for in situ applications, we would recommend liquid nitrogen as sample preservation method, along with the ZR Fecal DNA MiniPrepTM kit. Total bacterial DNA obtained by this strategy can be suitable for downstream PCR-based DNA analyses of swine feces.

Herbicidal Activities of Eupatorium adenophorum Extracts by 3 Extraction Methods

[ Objective ] The paper was to screen the better extraction method for herbicidal active substances of Eupatorium adenophorum. [ Method ] Three com- mon extraction methods, Soxhlet extraction, ultrasonic extraction and conventional extraction method, were used to prepare E. adenophorum extracts, and the herblcidal activity of E. adenophorum extracts extracted by 3 methods was studied by seed germination method. [ Result] The extraction rate of Soxhlet extraction was the highest of （22.54 ± 0.48 ）%, and the herbicidal activities of E. adenophorum extracted by Soxhlet extraction was relatively stronger. [ Conclusion] Soxhlet extraction was the better extraction method for herbicidal active substances of E. adenophorum.

Study on Extraction Method of Carotenoids from Citrus Leaves

In order to explore the extraction method of carotenoids from citrus leaves,the extraction effect of carotenoids from leaves of Honey pomelo by ultrasonic-assisted extraction was investigated by single factor experiment and orthogonal experiment.The results showed that the optimum extraction condition was:the ration of ethanol and acetone 1∶1(v/v,containing 0.1%BHT),solid-liquid ratio 1∶30(g/mL),extraction time 7 min,ultrasonic power 240 W,extraction frequency 3 times.Under the above condition,the extraction rate of carotenoids was 85.98%.

Screening of Extraction Methods for Glycoproteins from Jellyfish (Rhopilema esculentum) Oral-Arms by High Performance Liquid Chromatography

In order to select an optimum extraction method for the target glycoprotein （TGP） from jellyfish （Rhopilema esculentum） oral-arms, a high performance liquid chromatography （HPLC）-assay for the determination of the TGP was developed Purified target glycoprotein was taken as a standard glycoprotein. The results showed that the calibration curves for peak area plotted against concentration for TGP were linear （r= 0.9984, y=4.5895x＋47.601） over concentrations ranging from 50 to 400mgL^-1. The mean extraction recovery was 97.84% （CV2.60%）. The fractions containing TGP were isolated from jellyfish （R esculentum） oral-arms by four extraction methods： 1） water extraction （WE）, 2） phosphate buffer solution （PBS） extraction （PE）, 3） ultrasound-assisted water extraction （UA-WE）, 4） ultrasound-assisted P/3S extraction （UA-PE）. The lyophilized extract was dissolved in Milli-Q water and analyzed directly on a short TSK-GEL G4000PWXL （7.8 mm×300 ram） column. Our results indicated that the UA-PE method was the optimum extraction method selected by HPLC.

High Quality DNA Obtained from a Single Seed of <i>Vitis vinifera</i>L. Using Rapid DNA Extraction Method

Use of a single seed is very useful for genetic studies on Vitis vinifera. However, molecular markers require a fair amount of high purity DNA. Grapevine contains high concentrations of polysaccharides, polyphenols, tannins and other secondary metabolites. These compounds may hamper the DNA isolation processes and subsequent analysis. In this study we have compared two DNA isolation methods: the NucleoSpin Plant II method and a modified protocol from Doyle and Doyle. The average value of 260/280 nm absorption ratio, which is used to assess the purity of DNA and RNA was 1.8 (accepted as “pure” DNA) and 0.9 (presence of protein or other contaminants) for the first and second method, respectively. Using the NucleoSpin protocol, from a single seed (20 - 35 mg) we obtained an average yield of extracted DNA of 24.8 ± 5.2 to 38.4 ± 11.5 ng·mg-1 dry weight. Among the two protocols examined, the NucleoSpin method was more efficient and gave better quality of DNA values compared to those from the modified Doyle and Doyle procedures.

A Fast Extraction Method in the Applicaton of UHV Transmission Line Fault Location

To aim at the distribution parameter characteristics of UHV transmission line, this paper presents a fast extraction method (FE) to extract the accurate fundamentals of current and voltage from the UHV transmission line transient process, and locates the fault by utilizing two-end unsynchronized algorithm. The simulation result shows that this method has good performance of accuracy and stability, and has better location precision by comparing with results of one cycle Fourier algorithm. Therefore the method can efficiently improve the precision of fault location during the transient process, and makes the error of location results less than 0.5%.

Optimization of extraction method for quantitative analysis of Si/Al in soil phytoliths

Elemental information carried by phytoliths plays a crucial indicative role in geochemical research.For instance,it serves as an indicator of the carbon pool effect in phytoliths and aids in the elucidation of silicon sources.However,early extraction methods for soil phytoliths primarily focused on obtaining their morphological and quantitative information,lacking efficient techniques for quantitative elemental analysis.In this study,we aimed to extract Si/Al information from soil phytoliths.Considering the need for complete extraction of phytolith,six extraction methods were developed and further by alkaline dissolution to determine Si/Al.Six methods were compared in terms of enrichment capacity,the weight of extracted phytoliths,and Si/Al differences.The results indicated that the addition of Ammonia-Catechol in the commonly used heavy liquid flotation method effectively improved phytolith extraction capability and the accuracy of Si/Al results.Additionally,the inclusion of an acetic acid step before alkaline dissolution further removed surface-adsorbed impurities and enhanced the analytical quality of Si/Al in phytolith.The comparison of the data in this study with other published data shows that our method is relatively robust.The improved method proposed in this study can provide a new idea for the quantitative analysis of other elements in soil phytoliths.

A Comparative Study on Extraction Methods of Total RNA from Leaves of Acer truncatum ‘Luhong No.1’

Leaves of Acer truncatum ＇ Luhong No. 1 ＇ contain large amounts of polysaccharides and polyphenols, which seriously affect extraction yield and quality of total RNA. In order to explore the appropriate total RNA extraction method, total RNA was extracted from leaves of A. truncatum ＇ Luhong No. 1 ＇ with three methods, including kit method, Trizol method and modified CTAB method. The results showed that ODE6o/OD2so and OD^o/OD2ao ratios of total RNA extracted from leaves of A. truncatum ＇ Luhong No. 1 ＇ with kit method were higher than 1.8, with a general yield and certain level of DNA contamination ; OD^o/OD~ and OD^o/OD^o ratios of total RNA extracted with Trizol method were about 1.5, with the lowest yield; OD260/OD280 and OD260/OD230 ratios of total RNA extracted with modified CTAB method were about 2.0, with the highest yield and distinct eleetrophoresis patterns. The results demonstrated that total RNA extracted with modified CTAB method exhibited high yield and purity, which could meet the demands of subsequent molecular biology research. Thus, modified CTAB method is the appro- oriate method for extracting total RNA from leaves of A. truncatum ＇ Luhong No. 1 ＇

Screening of Extraction Methods for Protein from Potato Tubers

[Objectives]This study was conducted to screen different extraction methods for protein from potato tubers.[Methods]The bud eye,lateral and pith parts of Qingshu 168 and Kexin 1 were used as test materials,and were extracted by acetone extraction,trichloroacetic acid(TCA)extraction,salt extraction,alcohol extraction and phenol extraction,respectively.The protein contents of different parts were determined by spectrophotometry.A 2-factor randomized block design was used to study the effects of varieties,extraction methods,sampling parts and combinations of different factors on protein content.[Results]The protein contents of different varieties were different,and Qingshu 168 was significantly higher than Kexin 1(P<0.05),reaching 128.0 mg/L.The protein contents obtained by different extraction methods were different.Acetone extraction,salt extraction and TCA extraction showed no significant differences in the protein content,but they were significantly higher than phenol extraction and alcohol extraction(P<0.05).The protein contents obtained by the former three were in the range of153.3-159.7 mg/L.The protein content in the bud eye part of potato tubers was significantly higher than those in the lateral and pith parts(P<0.05),reaching140.7 mg/L.There were significant differences among different combinations of varieties,extraction methods and sampling parts(P<0.05).The comprehensive comparison showed that the salt extraction method was suitable for the bud eye part of Qingshu 168,and the TCA extraction method was suitable for the bud eye part of Kexin No.1.[Conclusions]This study provides a reference for potato protein extraction and further research.