Study on the green extraction of corncob xylan by deep eutectic solvent

Corn as one of the world's major food crops,its by-product corn cob is also rich in resources.However,the unreasonable utilization of corn cob often causes the environmental pollution,waste of resources and other problems.As one of the most abundant polymers in nature,xylan is widely used in food,medicine,materials and other fields.Corn cob is rich in xylan,which is an ideal raw material for extracting xylan.However,the intractable lignin is covalently linked to xylan,which increases the difficulty of xylan extraction.It has been reported that the deep eutectic solvent(DES)could preferentially dissolve lignin in biomass,thereby dissolving the xylan.Then,the xylan in the extract was separated by ethanol precipitation method.The xylan precipitate was obtained after centrifugation,while the supernatant was retained.The components of the supernatant after ethanol precipitation were separated by the rotary evaporator.The ethanol,water and DES were collected for the subsequent extraction of corn cob xylan.In this study,a novel way was provided for the green production of corn cob xylan.The DES was used to extract xylan from corn cob which was used as the raw material.The effects of solid-liquid ratio,reaction time,reaction temperature and water content of DES on the extraction rate of corn cob xylan were investigated by the single factor test.Furthermore,the orthogonal test was designed to optimize the xylan extraction process.The structure of corn cob xylan was analyzed and verified.The results showed that the optimum extraction conditions of corn cob xylan were as follows:the ratio of corn cob to DES was 1:15(g:mL),the extraction time was 3 h,the extraction temperature was 60℃,and the water content of DES was 70%.Under these conditions,the extraction rate of xylan was 16.46%.The extracted corn cob xylan was distinctive triple helix of polysaccharide,which was similar to the structure of commercially available xylan.Xylan was effectively and workably extracted from corn cob by the DES method.This study provided a new approach for high value conversion of corn cob and the clean production of xylan.

Adsorption behavior of activated carbon for the elimination of zearalenone during bleaching process of corn oil

Zearalenone is a mycotoxin produced by Fusarium species.It frequently contaminates cereals used for foods or animal feeds,especially deposited in crude corn oil.Certain amounts of zearalenone can be removed during refining processes.In this study,we studied the influence of activated carbon and six industial absorbents(zeolite,diatomite,attapulgite,perlite,montmorillonite and activated clay)on the elimination of zearalenone during bleaching process of corn oil and explored the absorption mechanism of activated carbon.Results showed that activated carbon had an excellent adsorption capacity of zearalenone compared with the other six industrial adsorbents.For activated carbon,a high removal rate of zearalenone(exceeding 83%)from heavily zearalenone-polluted corn oil was achieved and the removal rate of zearalenone was kept above 60%after five regeneration cycles.The research on the adsorption mechanism of activated carbon showed that Freundlich adsorption isotherm model and pseudo-second-order kinetic model could well described the adsorption process.The thermodynamic study demonstrated that adsorption process was spontaneous and exothermic.Fourier transform infrared spectroscopy and Raman spectroscopy further revealed that activated carbon was effectively combined with zearalenone viaπ-πinteraction.Thus,activated carbon is an efficient and suitable adsorbent to control the levels of zearalenone during bleaching process of corn oil.This study not only proposed a systematic research scheme for the mechanism study of activated carbon for the elimination of zearalenone in corn oil,but also provided the scientific basis for developing effective methods to eliminate zearalenone in refined vegetable oils.

Pr^(3+)掺杂的LaF3纳米微晶/氟氧化物玻璃陶瓷的4f5d能级光谱性质

用同步辐射的真空紫外(VUV)和紫外(UV)作为激发源研究了Pr3+(0·1%)掺杂的LaF3纳米微晶/氟氧化物玻璃陶瓷的4f5d能级光谱性质。样品中存在两种不同的Pr3+-LaF3微晶中的Pr3+最低的4f5d能级在1S0能级之上,玻璃中的却在1S0能级之下,通过VUV和UV激发光谱得出这两种Pr3+最低的4f5d能级的位置。当用181nm光激发样品时,在发射光谱中同时观察到了微晶中Pr3+4f2→4f2的窄谱带发射和玻璃中4f5d→4f2的宽谱带发射。在20K时观察到了LaF3纳米微晶中作为Pr3+光子级联发射(PCE)第二步的3P0→3H4的跃迁,室温下却没有观察到,文中详细讨论了产生这种现象的原因。

Factors Influencing Runoff P Losses from Farmlands of the Dianchi Lake Watershed in Yunnan, China

Effects of factors such as slope,surface soil texture,fertilization and crop cover with different rainfall intensities on phosphorus (P) losses in farmland runoff of the Dianchi Lake Watershed in Yunnan Province of China were studied through a rainfall simulation test using a red soil,one of the most widely distributed soils of the study area. Results showed that the runoff concentrations of total phosphorus (TP) and P losses differed with the slope,being highest when the slope was 18°. At two different rainfall intensities,the runoff TP and P losses had a similar decreasing trend as the surface soil texture became coarser,therefore applying the grit would decrease P in runoff from soils of farmland on slopes with heavier textures. With wheat as a crop cover the runoff TP concentrations and P losses were significantly lower than those of the bare soil. This showed that plant cover would greatly decrease P in runoff from the farmland of the study area. The TP concentration in runoff from the soil two days after fertilization doubled when compared with that from the non-fertilized soil,indicating that fertilization could mean a dramatic rise in P runoff if irrigation or heavy rainfall occurred immediately after application and that no fertilization before a rain and no irrigation immediately after fertilization would reduce runoff P loss from the farmland of the study area.

防护与舒适并存的新型抗机械冲击防护服

美国著名硅胶原料制造商Dow Corning公司最新研发了一款积极防护系统(Active Protection System)纺织品。该织物遇到冲击或压迫时会立即变硬,从而保护人体免受伤害,它同时还具备透气性、柔韧性、灵活性、轻便性、易护理性等许多传统防护服无法比拟的优点。这种智能型纺织材料具有很好的应用前景,不仅应用于摩托车及足球、曲棍球等某些运动项目的防护服上,而且在建筑工地、国防、军事等领域也将大有用途。

Changes of moisture distribution and migration in fresh ear corn during storage

Understanding of moisture changes in fresh ear corn(Zea mays L.)during storage is imperative for maintaining fresh corn quality.The changes of moisture distribution and migration in fresh ear corn during storage were investigated using low-field nuclear magnetic resonance(NMR)and magnetic resonance imaging(MRI).Water loss was greater than water migration in fresh ear corn within the first hour of storage;thereafter,water loss was weaker than water migration.With the extension of storage time,the signal intensity of MRI in different parts of sliced fresh corn with cob showed a downward trend,and the rate of signal intensity reduction was higher in the peripheral area than at the central part of sliced fresh corn with cob.The relative proportion of bound water increased with a concomitant drop in that of free water,when the total water content reduced in fresh ear corn under storage.In conclusion,NMR and MRI are useful and non-destructive tools for real-time monitoring of moisture distribution,migration,and loss in fresh ear corn during storage to assess its quality.These results can be used for future design of the preserving and processing conditions for fresh ear corn.

Preparation of dense Ta-LLZO/MgO composite Li-ion solid electrolyte:Sintering, microstructure, performance and the role of MgO

Cubic phase Li7La3Zr2O12(LLZO),a member of the Li–Garnet family,is a promising solid electrolyte and has been widely studied in recent years.However,LLZO samples prepared via conventional ambient air sintering reported in the published literature often contain large grains with lower than desired(<94%)relative density.In this study,a non-contact method of co-firing with mother powder method is proposed to prepare high-quality Ta-doped LLZO–MgO composite ceramics.By sintering at 1150℃for 5 h,the ceramics can reach relative density of 98.2%,conductivity of 5.17×10^-4 S cm^-1 at 25℃and fracture strength of 150 MPa.The sintered samples have uniform fine-grained microstructure and high critical current densities of 0.75–0.95 mA cm-2 at room temperature in Li–Li symmetry cell with Au modification.In addition,systematic sintering experiments and characterizations are conducted to explore the function of MgO in inhibiting the Ta-LLZO grain growth and its existing form inside the composite ceramics.

综合心理干预对社区慢性病患者的效果评价:一项源于社区的整群、随机、对照试验（英文）

背景:抑郁与焦虑经常出现在慢性躯体疾病患者中,通常这会加深这些躯体疾病所造成的损失,但是在中低等收入国家中这一问题却很少受到关注。目标:评估非专业临床人员和志愿者进行以社区为基础的心理干预对缓解慢性躯体疾病患者抑郁和焦虑症状的疗效。方法:将共计10,164名接受糖尿病或高血压治疗的上海社区居民任意分配到常规治疗组(n=2042)或干预组(n=8122),对干预组的干预包括社区范围的心理健康教育、同伴支持小组和个人咨询。采用自评患者健康问卷(Patient Health Questionnaire,PHQ-9)、广泛性焦虑量表(Generalized Anxiety Disorder scale,GAD-7)和12项健康状况调查问卷(12-item Short-Form Health Survey,SF-12)来评定基线和干预6个月后的抑郁症状、焦虑症状和生活质量。结果:8813人完成了基线评估,其中16%的人有轻度或较严重的抑郁或焦虑症状(PHQ-9或GAD-7>5),并有4%的人伴有中度或重度抑郁或焦虑症状(PHQ-9或GAD-7>10)。本研究有效实施了干预内容中的健康教育部分,但是在符合条件成为同伴支持小组的成员中仅31%的对象接受了干预措施,接受个人咨询的仅9%。本研究脱落率较高(51%),并且在完成和没有完成随访评估的人群之间存在显著差异。经过这些混杂因素的调整后,在完成两项评估的对象中,结果表明抑郁症状(F=9.98,p<0.001)、焦虑症状(F=12.85,p<0.001)以及SF-12中的心理部分总分(F=16.13,p<0.001)均得到显著改善。然而,自我报告未受控制的糖尿病或高血压的率没有显著变化。结论:这些结果支持了以社区为基础的干预措施的可行性,以降低在精神科人力资源有限的中低等收入国家中慢性疾病患者抑郁和焦虑症状的严重程度。然而,在确认该措施广泛大规模实施前还有大量方法学上的挑战需在未来研究中解决。

Migratory flight of insect pests within a year-round distribution: European corn borer as a case study

Insect migratory flight differs fundamentally from most other kinds of flight behavior, in that it is non-appetitive. The adult is not searching for anything, and migratory flight is not terminated by encounters with potential resources. Many insect pests of agricultural crops are long-distance migrants, moving from lower latitudes where they overwinter to higher latitudes in the spring to exploit superabundant, but seasonally ephemeral, host crops. The migratory nature of these pests is somewhat easy to recognize because of their sudden appearance in areas where they had been absent only a day or two earlier. Many other serious pests survive hostile winter conditions by diapausing, and therefore do not require migration to move between overwintering and breeding ranges. Yet there is evidence of migratory behavior engaged in by several pest species that inhabit high latitudes year-round. In these cases, the consequences of migratory flight are not immediately noticeable at the population level, because migration takes place for the most part within their larger year-round distribution. Nevertheless, the potential population-level consequences can be quite important in the contexts of pest management and insect resistance management. As a case study, I review the evidence for migratory flight behavior by individual European corn borer adults, and discuss the importance of understanding it. The kind of migratory behavior posited for pest species inhabiting a permanent distribution may be more common than we realize.

Identification and isolation of Mu-flanking fragments from maize

Transposable elements have been utilized as mutagens to create mutant libraries for functional genomics. Isolation of genomic segments flanking the insertion Mutator （Mu） is a key step in insertion mutagenesis studies. Herein, we adopted a modified AFLP method to identify and isolate Mu-flanking fragments from maize. The method consists of the following steps： 1） double-digestion of genomic DNA with Bgl II/Msp I and ligation of digested fragments to the Bgl II- and Msp I-adaptors; 2） enrichment of a subset of Bgl II/Msp I fragments followed by selective amplification of the Mu-flanking fragments; 3） simultaneous display of AFLP bands derived from the flanking regions for both insert and native Mu transposons; 4） identification and isolation of AFLP bands resulting from Mu insertions by comparing the banding profiles between Mu-induced mutants and their parental lines; and 5） confirmation of flanking fragments related to these Mu insertions. Using this approach, we have isolated flanking fragment（s） resulting from Mu insertion for every Mu-induced mutant, and one such fragment, M196-FF, is found to contain a partial sequence of the DNA topoisomerase I gene Topl. Moreover, the modified AFLP method including all restriction enzymes, adaptors and primers has been optimized in this study. The modified AFLP method has been proved to be simple and efficient in the isolation of Mu-flanking fragments and will find its usefulness in the functional genomics of maize.

Antifatigue,Antioxidant and Immunoregulatory Effects of Peptides Hydrolyzed from Manchurian Walnut(Juglans mandshurica Maxim.) on Mice

The Manchurian walnut(Juglans mandshurica Maxim.) is rich in proteins, whereas this resource has not been used efficiently. The antifatigue, antioxidative and immunoregulatory effects of Manchurian walnut hydrolysate peptides(MWHPs)were evaluated in this study. MWHPs with a degree of hydrolysis of 32.23% were ultrafiltered and divided into three fractions,namely, high(> 10 k Da), medium(3–10 kDa), and low molecular weight(< 3 kDa), and then fed to mice continuously at doses of 200, 400 or 800 mg/(kg·d). The antifatigue, antioxidative, and immunoregulatory effects of the peptides were tested on the second and fourth weeks of MWHP administration. Results showed that low-molecular-weight MWHPs exerted significant antifatigue(prolonging swimming time, elevating liver glycogen contents, and reducing lactic acid contents), antioxidative(enhancing superoxide dismutase(SOD), GSH-Px, and catalase(CAT) activities and reducing malondialdehyde(MDA) content), and immunoregulatory(raising the immune-organ index and promoting T-lymphocyte proliferation and s Ig A secretion in the intestinal tract) effects. This research indicates that MWHPs have potential applications in health care and may be developed as a base for new functional foods.

Molecular characterization of secaloindoline genes in introduced CIMMYT primary hexaploid triticale

In order to widen gene germplasm for kernel hardness in triticale, 60 synthetic hexaploid triticales were tested by the single kernel characterization system(SKCS) and secaloindoline alleles were identified by sequencing. Phenot^ing showed that frequencies of soft, mixed and hard genotypes were 43.3%, 48.3%, and 8.4%, respectively. Genotyping identified three known secaloindoline-a alleles and four known secaloindoline-b alleles. Three new Sina-Rl alleles were designated Sina-Rld, Sina-Rle and Sina-Rlf. Compared to Sina-Dlc, Sina-Rld showed four point mutations causing changes in four amino acids, Sina-Rle had one point mutation causing an alanine to glycine substitution, and Sina-Rlf possessed five point mutations but produced the same amino add sequence as Sina-Rld. Two new Sinb-Rl alleles were discovered and designated Sinb-Rle and Sinb-Rl/. Compared to Sinb-Rla, Sinb-Rle possessed a triplet-code insertion and four point mutations causing a cysteine insertion and two amino acid substitutions, and Sinb-Rl/possessed three point mutations causing a cysteine insertion and a change of arginine to glycine.Association of hardness index with secaloindoline alleles indicated t±iat SKCS of the Sina-Rld genotype was significantly lower than that of Sina-Rle, and Sinb-Rle was significantly lower than that of the Sinb-Rld genotype. A total of eight allelic combinations of secaloindoline genes were identified; Sma-Rld/Sinb-Rle and Sina-Rle/Sinb-Rld were relatively prevalent in the triticales surveyed. The results provide valuable information for further use of these germplasms in triticale breeding program due to the diverse polymorphism in secaloindoline genes.

Effects of Different Nitrogen Applications on Soil Physical, Chemical Properties and Yield in Maize (<i>Zea mays</i>L.)

Application of nitrogen (N) fertilizer is one of the most important approaches on improving maize grain yield. However, as is known to all, overuse N fertilizer not only leads to decline of N use efficiency and maize yield, but also leads to potential risk to environment pollution. This experiment was conducted to determine the effects of N fertilizer applications with nine different treatments on soil physical-chemical characters and maize grain yield using hybrid variety Zhengdan 958 in 2011 and 2012. Results indicated that the soil bulk densities of T2 (CK) and T1 were the lowest compared to other treatments in 2011 and 2012, respectively, whereas the soil bulk density of T5 in 2011 and T3 in 2012 were higher than other treatments. The soil porosity and field capacity of T5 in 2011 and T3 in 2012 were lower than other treatments, but those of CK in 2011 and T1 in 2012 were higher than other treatments. The pH values of T3 to T7 were lower than other treatments. These results indicated that the soil bulk densities were increased, whereas the soil porosity, field capacity and values pH were decreased by N application at different stages. N application could increase the N contents of leaf and stem, whereas less or excess N application should not significant improve maize yield. Although the soil organic matter and total N contents of T3 were the highest in both 2011 and 2012, the yield of T4 is the highest in both 2011 and 2012. The application amount, period and times of N fertilizer were important to maize yield.

Study on Isolation and Raman Spectroscopy of Glycinin in Soybean Protein

The secondary structures of soybean glycinin was investigated by Raman spectroscopy and its acidic and basic polypeptides were isolated. The results showed that the secondary structures of glycinin were mainly composed of 21.51% α-helix, 41.62% β-sheet,24.70% β-turn, and 12.18% random coil. For the disulfide bridge(—S—S—), the ratios were 34.8% gauche—gauche—gauche(g—g—g), 32.1% gauche—gauche—trans(g—g—t), and 33.1% trans-gauche-trans(t—g—t). The I_(850)/I_(830) intensity ratio of glycinin Raman tyrosine doublet confirmed that the contents of the N-buried and N-exposed tyrosine residue were 14.1% and 85.9%,respectively. The typical acidic subunit A and basic subunit B were clearly separated by heat denaturation and reduction withβ-mercaptoethanol, and their corresponding molecular masses were 42 and 38 ku, respectively. Raman spectroscopic analysis can be used to determine the secondary structural properties of glycinin. Further studies of the glycinin structures will be helpful for the utilization of soybean protein resources.

固体润滑剂改善摩擦衬片性能的考察

摩擦衬片和制动衬片一样必须具备一些摩擦学性能。这些性能——尤其是高而稳定的摩擦和低磨损率十分重要,因为这些衬片大多是保险部件。人们发现一些无机固体润滑剂和固体协同混合物在许多状况下对改善磨损率和摩擦系数之类的摩擦学性能起着重要作用。除含石棉的摩擦衬片外,无石棉的摩擦衬片还需要添加其它添加剂。本文对试验结果进行了讨论。

Resistance Analysis of 25 Corn Varieties to Stalk Rot and Evaluation of Yield Loss

Due to the meteorological factors, Henan Province had a large-scale outbreak of corn stalk rot in 2014, and the incidence status of 25 varieties was investigated. According to the relevant resistance identification standards, Xundan.509 was classified as resistance variety; Yudan606, Jinsai38 and Xundan3136 were classified as moderate resistance ones, while the other 21 varieties were highly susceptible varieties. Using the yield loss rate of 5% as the critical value of disease tolerance standard, XundanS09, Yudan606, Jinsai38, Xundan3136, Huaiyu5288, QiaoyuS, XY046, Zhengyu10, Lile66, WeikeT02 and Xundan29 were classified into tolerance varieties of corn stalk rot. The concept between disease resistance and disease tolerance was distinguished. The diseased plant rate was used as the classification basis of disease resistance and the yield loss rate was used as the evaluation standard of disease tolerance. The relationship between both was showed by a Venn diagram.

Glass Thickness and Fragmentation Behavior in Stressed Glasses

Breakage patterns, residual stress, and fractured surfaces on tempered glasses are investigated to find the correlation among glass thickness, tempered level, and the number of fragments, particularly when the glass thickness is less than 4 mm. Relatively thin glasses require high compressive stress for producing fragments, and the required compressive stress is increased with decreasing glass thickness (3.2 to 2.1 mm). By analyzing the residual stress of glasses before and after the fragmentation test, we observe that a relatively thin glass spends more stored energy to generate a new fracture surface and stores less energy for the second cracking as compared to thick glasses. Fractography shows that all glasses have a similar characterization on the fractured surface irrespective of glass thickness. However, the only dif- ference is the depth of the compressive layer. By reducing the depth of the compressive layer to less than approx. 20% of the glass thickness, it is observed that the possibility of producing small fragments is dramatically decreased. There- fore, this study confirms that the compressive stress and its depth are essential as key factors contributing to the achievement of a relatively high fragmentation using a thin glass.

Discussion on the Application of LS-DYNA in Superfine Grinding of Wheat Bran

Superfine grinding, involving the fragmentation mechanism of wheat bran cell tissue, is being employed by milling industry. In order to determine the effect of wheat bran cell tissue on the fragmentation mechanism when using superfine grinding,a technical scheme of the nonlinear finite element numerical simulation method based on LS-DYNA is proposed in this paper.The physiological characteristics of wheat bran structural layers including outer pericarp, intermediate layer and aleurone layer are examined first, and then the mechanical properties of wheat bran structural layers and their effects on the super fine grinding process are analyzed. Secondly, the explicit time integration algorithm of LS-DYNA is introduced, and the application feasibility of LS-DYNA in the analysis of wheat bran superfine grinding mechanism is discussed. Finally, the specific application of LS-DYNA in the determination of grinding form and load, the selection and design of the grinding media and the selection of grinding temperature are discussed in detail in the process of superfine grinding for wheat bran cell tissue. The above research provides a theoretical basis for selecting and developing the equipment and technology suitable for wheat bran superfine grinding, and lays a theoretical foundation for enhancing the quality and efficiency of wheat bran superfine grinding.

Effect of a near-zero magnetic field on development and flight of oriental armyworm(Mythimna separata)

The geomagnetic field affects all living organisms on the Earth.In this study we investigated the developmental and behavioral effects of rearing Mythimna separata in a near-zero magnetic field(<500 n T)compared to the local geomagnetic field(approximately 50μT).The near-zero magnetic field produced by a Helmholtz coil system significantly lengthened larval and pupal development durations,increased male longevity,and reduced pupal weight,female reproduction,and the relative expression level of the vitellogenin(Vg)gene in newly emerged females.Moreover,the near-zero magnetic field had a considerable negative effect on the mating ratio of M.separata adults.In addition,the moths in the near-zero magnetic field displayed less flight activity late in the night than those in the Earth's normal geomagnetic field,indicating that the flight rhythm of M.separata may be affected by the near-zero magnetic field.Reduction in magnetic field intensity may have negative effects on the development and flight of oriental armyworm,with consequent additional effects on its migration.

CPU主要散热材料——导热膏技术发展动向

随着市场上对微处理器的性能要求越来越高，对硅芯片级(siIicon leveI)功率消耗的要求也愈来愈高；此外，更小的机壳尺寸、更安静PC运作、以及更低硅晶体操作温度等的需求．共同形成了散热问题。为了加强散热效果．使用热导材料(Thermal Interface Materials．TLMs)将可有效降低热阻。