CFETR 25kW 4.5K氦制冷机RAMI初步分析

对25kW/4.5K氦制冷机进行了可靠性、可用性、可维修性和可监测性(RAMI)分析,建立了其可靠性框图,计算并评估了系统的可靠性和可用性。同时,通过故障、影响和危害分析指出了氦制冷机的故障模式,并提出了缓解和维护措施。

Optical and Mechanical Properties of Ramie Fiber/Epoxy Resin Transparent Composites

The residual resources of ramie fiber-based textile products were used as raw materials.Ramie fiber felt(RF)was modified by NaClO_(2) aqueous solution and then impregnated with water-based epoxy resin(WER).RF/WER transparent composite materials were prepared by lamination hot pressing process.The composite materials’color difference,transmittance,haze,density,water absorption,and mechanical properties were determined to assess the effects of NaClO_(2) treatment and the number of ramie fiber layers on the properties of the prepared composites.The results showed significantly improved optical and mechanical properties of the RF/WER transparent composites after NaClO_(2) treatment.With the increase of ramie fiber layers,the composites’whiteness,transmittance,and water absorption decreased while the haze increased.For material with three layers,the optical transmittance in the visible light region was 82%,and the haze was 96%,indicating the material has both high transmittance and high haze characteristics.The tensile strength increases with the increase of the number of layers,and the tensile strength of the composite with six layers is 243 MPa.This study broadens the scope of application of ramie fiber as a new option for home decoration materials.

Effects of Antimony Stress on Root Growth,Antimony Accumulation and Physiological Characteristics of Ramie(Boehmeria nivea(L.) Gaudich.)

[Objectives]This study was conducted to investigate the toxicity of heavy metal antimony(Sb) to ramie(Boehmeria nivea(L.) Gaudich.) and the tolerance response in ramie. [Methods] A pot experiment was conducted to study the effects of Sb stress on root growth and Sb accumulation and transport of the root system of cultivated ramie Zhongzhu No.1, as well as on the physiological characteristics of ramie leaves. [Results] The plant height and root dry weight and volume of Zhongzhu No.1 showed an effect of "promoting at low concentrations and inhibiting at high concentrations" with the increase of Sb concentration, and decreased significantly at the concentration of 4 000 mg/kg, but no obvious toxic growth symptoms were observed. The content of Sb in roots(289.7-508.6 mg/kg) and the root-shoot transfer factor(0.09-0.57) of Zhongzhu No.1 increased with the increase of soil Sb concentration, but the change of Sb bioconcentration factor in roots was opposite, indicating that high concentrations of Sb in soil could promote the absorption of Sb in roots and the transport of Sb to the aboveground part, but the Sb enrichment capacity of roots was relatively reduced with the increase of soil Sb. Sb stress had a certain impact on the physiological characteristics of ramie leaves. With the increase of Sb treatment concentration, MDA, POD and SOD showed a change trend of "first increasing and then decreasing", while CAT gradually increased, indicating that Sb stress caused changes in the physiological characteristics of ramie leaves, thereby affecting plant growth and development. [Conclusions] This study provides a theoretical basis for ecological restoration of ramie in mining areas.

Optimization for Microbial Degumming of Ramie with Bacillus subtilis DZ_(5) in Submerged Fermentation by Orthogonal Array Design and Response Surface Methodology

As a kind of natural fiber,ramie fiber has distinctive advantages in textile application,but the application is limited due to the traditional degumming mode.Compared with the traditional degumming process,the microbial degumming process has many advantages.To obtain the optimal conditions for degumming ramie with Bacillus subtilis DZ_(5)(BS DZ_(5)),a combined statistical approach of orthogonal array design(OAD)and response surface methodology(RSM)was used.The influences of initial pH of the bacteria medium,culture temperature,shaking speed,degumming time and inoculum size on submerged fermentation degumming were evaluated by using fractional factorial design.The main factors in the analysis were culture temperature,shaking speed and initial pH.The residual gum mass fraction was used as the optimization index,and the optimal conditions for degumming were determined by central composite design and RSM.Thus with only a limited number of experiments,an optimal ramie microbial degumming condition was found as the culture temperature of 40℃,the initial pH in the culture medium of 8.5,the shaking speed of 205 r/min,the degumming time of 96 h and the inoculum size of 5%.After microbial degumming of ramie under the optimal conditions,there was only 10.6%residual gum by mass in the fiber.In addition,the effective degumming of BS DZ_(5)was also confirmed by a scanning electron microscope(SEM).

Growth and Antimony Bioconcentration Characteristics of Wild Ramie(Boehmeria nivea)under Sb Stress in Different Valence States

[Objectives] To explore the effects of antimony(Sb) in different valence states on the growth and Sb bioconcentration and transfer of wild ramie(Boehmeria nivea). [Methods] A pot experiment was conducted to study the effects of Sb(Ⅲ) and Sb(Ⅴ) stress on plant height, biomass, leaf SPAD value, Sb contents in various organs, Sb bioconcentration and transfer factors, and other indexes. [Results] Both kinds of Sb treatments showed a trend of "first increasing and then decreasing" in plant height as Sb concentration increased. The plant heights in Sb(Ⅲ) treatments with a concentration lower than 1 000 mg/kg and Sb(Ⅴ) treatments with concentrations lower than 4 000 mg/kg were significantly higher than that of the control check(CK);and the Sb(Ⅲ) treatment of the high concentration(4 000 mg/kg) resulted in a significant decrease in plant height, while the 8 000 mg/kg Sb(Ⅴ) treatment still showed an increase in plant height, indicating that the toxicity of Sb(Ⅴ) to wild ramie was significantly lower than that of Sb(Ⅲ). The Sb(Ⅲ) treatments with a concentration lower than 2 000 mg/kg had little effect on the dry weight of the aboveground part, while the treatment with a higher concentration showed a significant decrease;and the dry weights in various concentrations of Sb(Ⅴ) treatments showed no significant differences, but they were significantly higher than the CK and corresponding concentration of Sb(Ⅲ) treatment. Both types of Sb stress could promote the increase of SPAD value in wild ramie leaves, and the performance was significantly higher than the CK. As the concentration of Sb treatment increased, the Sb content in both the aboveground and underground parts showed a significant increase;and the comparison of Sb content under corresponding concentrations of the two types of Sb treatments showed that in the aboveground part, Sb(Ⅲ) was higher than Sb(Ⅴ), while in the underground part, the opposite was true. The bioconcentration factor(BF) of Sb decreased with the increase of Sb treatment concentration overall, and the value of Sb(Ⅴ) was smaller than that of Sb(Ⅲ), but both kinds of Sb stress were significantly smaller than the CK. The transfer factor(TF) of Sb in wild ramie showed a trend of "increasing first and then decreasing" with the concentration of Sb treatment, and various treatments of Sb(Ⅲ) were higher than the CK, with significant differences, while among various treatments of Sb(Ⅴ), except treatment B3, the reduction of which was not significant, other Sb(Ⅴ) treatments showed significant decreases. Comparing the two types of Sb treatments, the BF and TF values of Sb in wild ramie under Sb(Ⅲ) treatments were higher than those under Sb(Ⅴ) treatments, and the TF reached a significant level, indicating that the Sb transport ability of wild ramie under Sb(Ⅲ) treatments was stronger. [Conclusions] This study provides a theoretical basis for the mining of wild ramie Sb restoration genes and the application of large-scale cultivation in ecological restoration.

In-situ Elimination Effect on Heavy Metals in Contaminated Soil from the Mining Area by Ramie

[Objective] The aim was to study on in-situ elimination effect on heavy metals in soil of the mining area by ramie （Boehmeria nivea （L.） Gaud.）. [Methods] Based on Xiangzhu No.3 and Zhongzhu No.1, we conducted research on heavy metals contents of plants growing in soil of Qibao Mountain orefield in Liuyang, Hunan Province, and on characteristics of enrichment and transfer of heavy metals （Cu, Pb, Cd, Zn） under influence of the two ramie species. [Result] It was concluded that trend of Cu content in different parts of ramie was as follows： rootskinleafbone; trend of Pb was rootleafskinbone; trend of Cd was rootskinboneleaf; the trend of Zn was rootskinboneleaf. In farmland A （with low content of heavy metal）, for per square meter of plough horizon, effect of Zhong 1 on heavy metals transferring volume and the period for restoration of the soil into national standard one （Category Ⅲ of Environmental Quality Standard for Soil） have been concluded. Specifically, for Cu, the corresponding values were 3 404.44 mg and 8.59 y, respectively; for Pb, the values were 3 638.5 mg and 13.52 y; for Cd, the values were 720.48 mg and 1.49 y; for Zn, the values were 37 324.8 mg and 0.67 y. [Conclusion] Soil contaminated by Cu, Pb, Cd, and Zn in orefield can be rapidly restored by growing ramie.

Analysis of Climatic Factors Causing Yield Difference in Ramie among Different Eco-regions of Yangtze Valley

[Objective] This study was to investigate the climatic factors affecting the regional eco-adaptability of ramie.[Method] Five experimental sites of different eco-types in ramie growing regions in Yangtze Valley were set up to investigate the yield of Zhongzhu No.2,based on which we assessed the adaptability of Zhongzhu No.2 to various eco-regions and further analyzed the climatic factors causing the difference in eco-adaptability.[Result] Ramie yield varied largely among various experimental sites and the yield difference appeared to be well repeatable,with a differential value between the maximum and the minimum reaching 2.3 kg/20 m2.Analysis of the yield data,together with climatic factors in various ecological regions showed that yield of Zhongzhu No.2 was significantly correlated with rainfall,sunshine hours,relative humidity during its growing period.Of the climatic factors,sunshine hours and rainfall can positively promote yield increase,while relative humidity negatively regulate ramie yield.[Conclusion] The climatic indices,including rainfall,sunshine duration and relative humidity are a key factor causing yield difference in ramie among different regions of Yangtze Valley.

SOME END-USES OF PURE RAMIE NOIL ROTOR YARNS

In the previous studies, the optimum technological combination has been obtained for producing coarse pure ramie noil yarns on rotor spinning system currently. Because of no yarn properties standard available at present for suchlike yarns, it is considered necessary to analyse the acceptability of coarse pure ramie noil rotor-spun yarns in terms of yarn properties before their products being developed. By the aid of a hypothetical concept "pure ramie noil ring-spun yarn", this paper draws the conclusion that the coarse pure ramie noil rotor-spun yarns are condsidered acceptable to a great extent; furthermore, it introduces 5 kinds of woven fabrics and 3 kinds of knitted fabrics successfully designed and developed from those yarns.

THE INFLUENCE OF COMBING ROLLER SPEED ON PURE RAMIE NOIL ROTOR YARN QUALITY AND SPINNING PERFORMANCE

This paper reports the optimum design of combing roller speed with reference to yielding 6-13 Ne(98.4—45.4 tex) pure ramie noil rotor-spun yarns. The universal rotatable composite design is adopted to get the highly precise regression equations, in which the variables are combing roller speed and yarn linear density considered to be the main technological parameters of combing roller and, the responses are the evaluation indexes concerning spinning stability, fiber length distribution of fibre ring from rotor groove and yarn properties. Based on these regression equations, the contours are plotted to analyse the influences of the parameters on the evaluation indexes; the optimization multicriteria mathematical model is simultaneously established to obtain the optimum parameters with the aid of Object Programming Approach along with Constrained Random Ray Method. Finally, an experiment is carried out to further test the acceptance of the calculated optimum values. It is shown that, for any yarn linear density within 6—13 Ne (98.4—45.4 tex), combing roller speed varying from 5000 to 9150 r/min affects content of extra-long fibre in fibre ring from rotor groove and yarn properties but does not significantly influence spinning stability; 7075 r/min, at which the SAQ-12 type of saw-toothed combing roller runs, is recommended to be the optimum combing roller speed for producing 6—13 Ne (98.4—45.4 tex) pure ramie noil yarns, where a compromise is achieved among the lowest content of extra-long fibre in fibre ring, the best spinning stability and the best yarn properties.

Mechanism of exogenous selenium alleviates cadmium induced toxicity in Bechmeria nivea(L.) Gaud(Ramie)

The protective role of exogenously supplied selenium （Se^6＋） on Bechmeria nivea （L.） Gaud （Ramie） subjected to cadmium （Cd） stress was studied in vitro, and the mechanism was discussed by investigating plant growth, malondialdehyde （MDA）, activity of antioxidative enzymes and DNA methylation pattern. Plants grown in hydroponic culture were supplied with spraying Se （selenate, 1.2μmol/L） and cadmium （Cd（NO3）2, 0, 3, 6 and 9 mg/L）, individually or simultaneously. At low Se spraying levels, SOD activity was increased by 35.34%, 43.18%, 3.63%under 3, 6 or 9 mg/L cadmium contents, POD was increased by 12.45%, 14.14%, 3.27%, and the level of DNA methylation was decreased by 10.70%, 18.18%and 15.59%, respectively. The results confirmed that spraying low Se on ramie leaves could enhance the activity of SOD and POD, and regulate DNA methylation in ramie leaves.

Genetic Relation Analysis on Ramie[Boehmeria nivea(L.)Gaud.]Inbred Lines by SRAP Markers

The objective of this article is to reveal the variations of ramie inbred lines in DNA level and discuss their molecular background to provide a theoretical basis for ramie cross breeding. In the present study, the genetic relationships among 33 inbred line accessions and two wild types that originated from China and Brazil were estimated using sequence-related amplified polymorphism （SRAP） markers. The results showed that 33 out of 81 primer combinations turned out to be polymorphic and 332 polymorphism bands were obtained. On the basis of the appearance of the markers, the genetic relationships were analyzed using unweighted pair-group method of arithmetic average cluster analysis （UPGMA）, and the genetic Jaccard similarity coefficients were calculated. The inbred-lines originating from China and Brazil formed a cluster suggesting a possibility that the Brazilian cultivars could have developed from cultivars introduced from China. Within ramie inbred-lines, the groupings also indicated that the greatest genetic relationship among cultivars was correlated to the region of origin of cultivars. The results provided the evidence that SRAP was an efficient approach, suitable for taxonomic analysis of ramie inbred lines, To the authors＇ knowledge, this is the first application of SRAP marker on the systematics of ramie inbred lines.

基于RAMI 4.0解读新一代智能制造

为了深入认识中国工程院"基于新一代人工智能的‘中国智能制造发展战略研究报告’"的重要意义,笔者采取了解构和重构的方法,对德国工业4.0参考架构模型(RAMI 4.0)进行了剖析,并与中国工程院报告中提出的智能制造总体架构做了对比,发现了彼此的相同和差异之处,认为中国版智能制造总体架构在智能程度上更胜一筹,这是中国人对智能制造发展的贡献。同时该分析过程亦加深了对二者的认识。

Effect of Planting Density and Fertilizer Application on Fiber Yield of Ramie (Boehmeria nivea)

As the most important cultural practices for ramie （Boehmeria nivea） production, the single effects of plant density and nitrogen （N）, phosphorus （P）, potassium （K） fertilization on yield are well documented. To achieve the high yield and quality of ramie fiber, it is principal to quantify the fertilizer dosage for ramie sustainable production. A central composite design （CCD） was adopted with three replications, for a two-year field experiment （2008-2009） in the Yangtze River Valley of China. The aim was to evaluate both the individual and combined effects of plant density and N, P, and K fertilization on yield and fiber quality. The effects of the four factors on yield and quality of ramie cultivar Huazhu 4 were tested. Then mathematical models of the relationship among the four factors affecting ramie production and quality were established and analyzed to optimize the four factors, and used to establish optimum cultivation methods for the elite cultivar suitable to this area of the Yangtze River Valley. Supplements of N （X2）, P 0（3） and K 0（4）, and the density （X0 with N （X2） interaction significantly influenced strength in tests of mature ramie. The influence on fiber yield in the two year tests by the four factors ranked as follows： X3〉X4〉X~〉X2. We established the optimization technique attaining yield of 2 600 kg ha-~ in the tests as following： density of 28 350-31 650 plants ha-1, and supplements of N, P and K of 363-387, 98.58-105.48 and 280.20- 319.8 kg ha-1, respectively. It was concluded that nitrogen mostly improved plant growth and fiber yield while potassium had discernible effects on fiber quality.

Chemical Composition and Nutritive Value of Ramie Plant [Boehmeria nivea （L.） Gaud] and Its By-Products from the Textile Industry as Feed for Ruminants

In order to verify the possible use of ramie as feed for ruminants, a study was undertaken on the chemical and nutritional evaluation of different parts of this plant. Four stocks of samples picked up in two different periods （summer and autumn） were analyzed. The standard chemical composition was determined on the whole plant and on its parts, the study was particularly focused on leaves and tops, not used in fibre production and available as livestock feed. Organic matter enzymic digestibility （OMD） was determined on all the samples by a double step method based on cellnlolytic andproteolytic enzymes. The chemical analysis showed good crude proteins content in leaves, tops and whole plant： 17.00 ~ 1.52%, 15.25 ~ 0.77% and 11.79 ~ 3.32% on dry matter （DM） basis respectively and good acid （ADF） and neutral （NDF） detergent fibre fractions. Lignin and ash resulted high in all plant parts and organic matter （OM） was consequently low, ash analysis showed high calcium concentration, especially in leaves, with values exceeding 4% of din, whereas the other micro （except the lead） and macroelements were in a normal range. OMD and energy values resulted poor in leaves, tops and in the whole plant and lower than the other forages commonly used as feed for runninants, thus the utilisation of ramie plant and its by-products requests further investigations.

Study on the Relationship Between Sex Differentiation and Ethylene in Ramie

To explore the role of ethylene in sexual determination in ramie, the ethylene release rates in ramie stem apex of different sex, bud of the same node in female and hermaphrodite ramie in the second crop, and single inflorescence of different sex in hermaphrodite ramie were measured by gas chromatography. Effects of two ethylene inhibitors on sex expression in ramie were investigated. The ethylene release rate of stem apex was higher in the second crop or female ramie than that in the third crop or hermaphrodite ramie during growth. Although ethylene release rates between lower nodes and higher nodes were little different, it was lower in the middle nodes in hermaphrodite ramie. The ethylene release rates were higher in the higher nodes of female ramie at the second crop. At the third crop, the ethylene release rates were higher in lower nodes, lower in middle nodes and then highest in higher nodes in female ramie. However, an opposite ethylene release pattern was observed in hermaphrodite ramie. The ethylene release rate was higher in female flower than male flower and mixed inflorescence in hermaphrodite ramie. The male flower could be distinctly induced by AVG （aminooethoxyvinylglycine）. The node of the first male flower, percentage of female flowers and ratio of female flowers to male in ramie were evidently depressed by AVG in contrast to water. The percentage of mixed male and female flowers was also increased and the percentage of female flower decreased by spraying AgNO3. There was a close relationship between sexual differentiation and ethylene release rate in ramie. The female ramie could be induced by high ethylene release rate. The female flower could be inhibited by AVG and AgNO3. AVG at a concentration of 300 mg L^-1 was most effective.

Mechanical and Thermal Properties of Apocynum and Ramie Fiber Mat Reinforced Polylactic Acid Composites

With the increasing awareness of environmental protection and rational utilization of resources,natural fiber reinforced composites have shown broad development prospects.Apocynum fiber,known as the“king of wild fiber”,not only has moisture absorption,air permeability,and good mechanical properties but also has many health-related advantages such as antibacterial properties.In this study,four types of needle-punched Apocynum fiber and ramie fiber mat reinforced polylactic acid(PLA)composites were fabricated.Mechanical and thermal properties of the composites were tested and analyzed.The results showed that compared with those of the ramie fiber finish needle-punched mat reinforced composites,the tensile strength and the tensile modulus of Apocynum fiber finish needle-punched mat reinforced composites had increased by 15.3%and 60.1%,respectively.In comparison,the bending strength and the bending modulus were decreased by 21.8%and 7.6%,respectively.Moreover,compared with the Apocynum fiber finish needled-punched mat reinforced composites and the ramie fiber finish needle-punched mat reinforced composites,the Apocynum 50/ramie 50 finish needle-punched mat reinforced composites had the best tensile and bending properties.The after-fracture morphology was detected by a scanning electron microscope(SEM).The thermal properties of the composites were also characterized.It was found that the thermal properties of the four types of composites showed very similar behaviors.

Cloning and Expression of Key Enzyme Gene GalAT in Ramie Pectin Biosynthesis

To isolate the cDNA partial sequence of key enzyme gene GalAT for pectin biosynthesis in ramie [Boehmeria nivea （L.） Gaud], and thus to understand the expression of GalAT gene in different tissues of ramie, degenerate primer was designed according to GalAT conserved sequence in other species reported, and the cDNA sequence of GalAT gene from ramie variety Zhongzhu 1 was cloned by RT-PCR method based on the degenerate primer. The cDNA revealed a 986-bp in length which encoded 328 amino acids. The cDNA sequence and putative amino acid sequence of GalAT shared high identity with previously reported Arabidopsis thaliana GA UT4 （GalAT） as 77 and 83%, respectively. Molecular evolution analysis showed that the putative amino acid sequence and Arabidopsis thaliana GAUT4 gathered to a same group. Real-time quantitative PCR analysis showed that GalAT mRNA accumulated most abundantly in root, and GalAT transcripts in all kinds of ramie tissues in turn revealed as follows： root 〉 leaf〉 bast 〉 or ≈ xylem.

Effects of Nitrogen Application on Osmotic Adjustmentof Ramie (Boehmeria nivea L.) with Different NitrogenEfficiency

Ramie (Boehmeria nivea L.) is one of the most important fiber crops and biomass materials. However, previous studies showed that ramie presented a very low nitrogen agronomy efficiency (NAE, 23.2%~27.8%) in traditional farming, and the nitrogen fertilizer was applied excessively in ramie field. Plant osmotic adjustment (OA) responses to environmental stresses positively and exhibits improvements in plant tolerance. Whereas results varied due to the complexity of plant-environment interactions and lack of insights of specific species. In order to improve ramie production through osmoregulation, our current study investigated the role of nitrogen application and osmotic adjustment in improving the growth and yield in two varieties of ramie (H2000-03 and Ceheng Jiama) with contrasting nitrogen use efficiency (NUE) grown at 5 different N rates including N0, N6, N9, N12 and N15;0, 6, 9, 12 and 15 mmol/L N, respectively. The results showed that ramie adapted to different nitrogen rates through OA and significant differences of osmolyte content between varieties only presented at the particular growth stage. Obvious inflexion of yield, osmolyte content involving proline, soluble protein (SP), soluble sugar (SS) and malonaldehyde (MDA);nitrogen sensitive index (NSI) and comprehensive evaluation (D) in both varieties were observed. Our results recommended that the overall lifting of OA at a lower N level and at the proper growth stage would be a reasonable approach for improving ramie NUE.

Prediction of Crude Protein in Ramie by Near-Infrared Spectroscopy(NIR)

[Objective] This study was conducted to evaluate the feasibility of deter- mining crude protein in ramie using near-infrared （NIR） spectrometer. [Method] Par- tial least square regression （PLSR） was performed to establish a calibration model based on 50 samples for predicting the crude protein content in ramie, and the model was validated with data in the validation set consisting of 10 samples. [Result] The correlation coefficient of the model was 0.98. There was a good correla- tion between the predicted values by the near-infrared prediction model and the measured values by chemical analysis, and the relative error was 3.54% on aver- age between the predicted and the measured values. [Conclusion] The results showed that it is feasible to determine crude protein content in ramie using NIR spectroscopy-based prediction model.

Report on Screening Test of Dazhou Superior Ramie Germplasm Resources

[Objectives]To promote the development of the ramie industry in Dazhou City of Sichuan Province and provide a material basis for the breeding of new ramie varieties.[Methods]The Institute of Bast Fiber Crops of Dazhou Academy of Agricultural Sciences performed a screening test of excellent ramie germplasm resources from 2017 to 2019 to compare the growth,resistance,raw fiber yield and fiber fineness of the experimental materials.[Results]All the experimental materials showed strong growth potential,drought resistance and disease resistance.There were 8 kinds of resources with a fiber fineness greater than 2000 m/g,of which 3 kinds of resource materials had a fiber fineness greater than 2300 m/g;12 kinds of resources has the raw fiber yield exceeding the control and 10 kinds of resources had the raw fiber yield≥2000 kg/ha;3 kinds of resources met the requirements of the high-yield and high-quality indicators(fiber fineness exceeding 2000 m/g and raw fiber yield≥2000 kg/ha),they were BD0718,BD1614 and BYL2.[Conclusions]These high-quality ramie resources can provide a rich resource base for the breeding of new ramie varieties.