Influence of technological processing on various nutritional characteristics of sunflower protein isolates

The composition and nutritional value of sunflower meals and protein isolates were determined. One of the meals was an ordinary industrial one (HI) and the other (HL) was prepared at the laboratory from the same batch of sunflower seeds. The protein isolates were obtained from both meals (AHI and AHL, respectively) and from the original seeds (AS), by means of a process employing water extraction and precipitation at pH 4.3. Chemical analysis of both meals showed that their moisture, protein crude fiber and fat contents had no significant difference. Sulphur amino acids (g/16 g N) were higher in the isolates than in the flours. The HL flour, and the AHL and AS isolates had a higher proportion of available lysine (96.9%, 93.0%, and 92.4% respectively) than the HI flour and AHI isolate. This improvement of protein quality was attained by the employment of less drastic thermal treatments in their preparation, as compared with the treatments to which other materials were submitted.     

Post-reaction strength of coke under various conditions

The post-reaction strength of coke was studied at different reaction temperatures in CO₂ and mixed gas atmospheres. The influence of solution loss conditions on post-reaction strength of coke, with different levels of reactivity, was studied in this paper.     

Visual color matching under various viewing conditions

In this article, we provide colorimetry data for which it was judged that the colors between different media matched under various viewing conditions. Painted color patches, a monitor, and printed color patches were used in the color matching experiments, in which we compared the appearances of the painted color patch and the monitor, or the monitor and the printed color patch, using the method of constant stimuli. The nine types of viewing conditions we used could be envisaged to occur when comparing different device outputs indoors. The experimental data obtained were compared with corresponding colors predicted with the use of five types of color appearance model, including color appearance formulae. We found that when the viewing conditions were the same for the different media, there was good agreement between the experimental data and the CIECAT94 model. And by adjusting the brightness induction and the chromatic induction factors, it was possible to improve conformity for the lightness and the chromaticity. Moreover, it was possible to improve the white point shift, which cannot be adjusted with the use of optimized parameters by introducing incomplete adaptation. By optimizing the parameters and introducing incomplete adaptation, it is possible to make the mean color difference ΔE between the corresponding color and the color matching point less than 10 CIELAB units for all of the viewing conditions.     

Prediction of color appearance under various adapting conditions

A model of color vision is given to predict color appearance of object colors under various illuminants and illuminance levels. The model constitutes a uniform color-appearance space under any adapting condition, and can predict the metric quantities relating to the following color perceptions: (1) constant-hue loci, (2) the Munsell color scheme, (3) the increase of brightness contrast of nonselective samples with increasing adapting-illuminance level, (4) the Helson-Judd effect, and (5) the increase of colorfulness of chromatic samples with increasing adapting-illuminance level.     

Adsorption behavior of aqueous europium on kaolinite under various disposal conditions

This work investigated the adsorption behavior of europium on kaolinite under various disposal conditions. Batch-wise adsorption and precipitation experiments and equilibrium model calculations were performed over a pH range of 4–10 and CO₂ concentration range of 0%, 0.03%, and 10%. Experimental precipitation behaviors are in agreement with the results of equilibrium model calculations using the geochemical code MINTEQA2. Aqueous species of Eu³⁺ exists mainly at pH 5 or below and solid phases of Eu(OH)₃(s), Eu(OH)CO₃(s), and Eu₂(CO₃)₃·3H₂O(s) are formed at higher pH ranges. Adsorption behavior of Eu on kaolinite in the low pH range can be explained by interlayer ion-exchange reaction. The significant increase in adsorbed amount at pH 5–6 is due to the surface complexation at the edge site of kaolinite. In the high pH range, precipitation of Eu contributes mainly to the adsorption quantity. The rapid decrease in adsorbed amount above pH 7 under 10% CO₂ condition occurs by the formation of anionic europium species of Eu(CO₃) ₂ ^- .The adsorption of Eu on kaolinite could be well interpreted by the Freundlich adsorption isotherm. The data except for the highest equilibrium concentration ranges were also explained by Langmuir isotherm and the maximum adsorbed quantity of Eu on kaolinite,b, is 1.2 mg/g.     

Studies on the effectiveness of various sulfur fertilizers under controlled conditions

Three factorial experiments with four replications were conducted in a greenhouse to examine the effectiveness of gypsum, elemental sulfur (ES powder) and three S containing N fertilizers, viz., ammonium sulfate (AS), urea + ES, and Ureas (20% AS and 80% urea). All experiments were conducted twice in different years.In the first experiment with uncropped soil, the effects of soil type, leaching rate (2.3 and 6.9 mm water per day) and urea addition on sulfate leaching losses were studied. Leaching losses decreased in the order Ureas > ammonium sulfate (AS) > gypsum urea + ES. Increasing the leaching rate greatly increased sulfate losses from both soils. Losses were greater in the sandy Typic Hapludoll than in the clayey Oxic Paleustalf. Sulfate adsorption was found to decrease strongly with rising the pH in both soils. Hydrolysis of urea temporarily raised the pH of the soil, thereby increasing the sulfate leaching losses.In the second experiment the effects of S rate (0–65 mg per kg soil), split application and leaching rate (0 and 2.3 mm per day) on sulfate leaching losses and apparent S recovery (ASR) by three successive cuts of ryegrass (Lolium perenne L.) were studied. Herbage yield more than doubled when S was applied. The effectiveness of the sulfate fertilizers was greater when S was split-applied than given all at once. With split applications the ASR decreased in the order: Ureas > AS > gypsum > urea + ES > ES powder. ES fertilizers were least effective, because the oxidation rate of ES to sulfate was clearly too slow.In the third experiment the effects of S rate (0–40 mg per kg soil) and split application on sulfate leaching losses and ASR in the grain of wheat (Triticum aestivum L.) were studied under leaching conditions (2.3 mm per day). Grain yield increased strongly due to S application. Split application greatly increased the effectiveness of the sulfate fertilizers and appeared to be an effective tool in satisfying the S need of the crop under leaching conditions. Again, ES fertilizers were least effective, because the oxidation rate of ES was too slow to meet the S demand of the crop.In all experiments leaching losses of sulfate from the ES fertilizers were smaller than from the sulfate fertilizers.     

高温高压下金刚石同质外延生长的研究

文章在铁镍-石墨体系中,对金刚石晶形在不同生长条件下的形成过程进行了研究,并通过对合成晶体的形貌分析,进一步推测金刚石晶形的形成过程。实验中发现,后期合成晶体的晶形与前期合成晶体的晶形以及表面粗糙程度有着密切的联系;金刚石晶体在光滑完整的表面生长速度较快,而且合成晶体的晶形较为规则;不具备完整晶形的晶体在生长后期也能通过自身调节形成具备完整晶形的晶体,但合成晶体的规则性较差,表面容易出现缺陷,而且体系中出现大量自发核,为进一步了解金刚石的同质外延生长,以及金刚石晶体晶形的形成过程提供了一种新途径。     

Effects of inorganic anions on photoactivity of various photocatalysts under different conditions

The effects of inorganic anions (SO₄^2?, H₂PO₄^?, HCO₃^?, F^?) on the photoactivity of surface bond‐conjugated TiO₂/SiO₂ and Fe–TiO₂/SiO₂ for the photodegradation of Acid Red B were investigated. The introduction of iron changed the chemical environment of lattice titanium and the surface charge properties of TiO₂/SiO₂. Fe–TiO₂/SiO₂ inhibited the negative role of the selected inorganic anions. The effects of different light sources and dyes of various structure, with a sulfonate group, on the role of F^? in decolorization of Acid Red B were examined. F^? has the same negative influence on the photoactivity of TiO₂/SiO₂ with the blacklight lamp and solar irradiation, but shows no influence upon irradiation with the 254 nm lamp. The tested inorganic anions affected the photodegradation of dyes by controlling their adsorption onto the surface of the catalyst and by trapping h⁺ and ^?OH. Copyright © 2004 Society of Chemical Industry     

Dietary factors and aflatoxin toxicity: I. comparison of the effect of two diets supplemented with aflatoxin B1 upon two different strains of rats

Previous studies in this laboratory with rats fed low levels of aflatoxin as a component of peanut discards, suggested either a strain tolerance for aflatoxin or a possible protective factor present in the diets used. In this study, two strains of rats, the Charles-River strain and the former USC strain, were used to test the effect of 1.7 ppm purified aflatoxin B₁ included for 3 months in two different diets; one previously used in this laboratory and one used by other investigators in aflatoxin studies. After an experimental period of either 12 or 18 months, growth, mortality, gross pathology, and organ wt were measured, and histopathological examination and biochemical analyses were performed. Plasma and liver cholesterol levels, total liver lipids, and fatty acids in the various lipid fractions of plasma, liver, and liver tumor lipids were measured. Both strains of rats proved to be susceptible to aflatoxin toxicity at this level as manifested by the appearance of hepatomas; however, liver involvement was more extensive in the Charles-River rats. The diet used by other investigators produced symptoms similar to those observed as a result of essential fatty acid deficiency and also affected the response to aflatoxin through an aggravation of symptoms, i.e. an inhibition of growth and increased size and severity of the liver tumors.     

不同储存条件对结核亚单位疫苗参考品免疫原性的影响

目的评价不同储存条件对结核亚单位疫苗参考品(简称参考品)免疫原性的影响。方法按以下抗原与佐剂比例配制1人份疫苗参考品:[10μg Ag85b蛋白+10μg EC蛋白+50μg Ploy IC+0.2 mg Al(OH)3]/0.2 ml。将疫苗参考品于-70及4℃分别保存1、6、9、12个月,并于每个时间点免疫BALB/c小鼠,实验分4组:PBS组、冷藏组(4℃保存参考品)、冻存组(-70℃保存参考品)及现配组,均经小鼠后肢内侧肌肉注射,0.2 ml/只,共免疫3次,每次间隔10 d,末次注射10 d后,收集小鼠脾淋巴细胞,并经眼球采血,分离血清。ELISPOT法检测抗原特异性的IL-2、IFNγ水平,CCK-8法检测细胞增殖水平,间接ELISA法检测血清Ig G抗体效价。结果经Ag85b和EC刺激,现配组各月间的斑点形成细胞数(spot forming cells,SFCs)及脾细胞增殖指数(stimulating indox,SI)差异无统计学意义(P0.05),且均显著高于PBS组(P0.05),表明免疫学检验模型成立且稳定,各试验组与现配组结果具有可比性。经4℃冷藏12个月,参考品的Ag85b及EC特异性IL-2、IFNγ相对水平及脾淋巴细胞相对增殖水平均显著低于冷藏1个月的参考品(P0.01),经-70℃冻存12个月,参考品的Ag85b、EC特异性IL-2、IFNγ相对水平及脾淋巴细胞相对增殖水平与冻存1个月的参考品差异无统计学意义(P0.05)。与现配组比较,冷藏组及冻存组Ag85b和EC特异性抗体水平相对平稳,各月间差异均无统计学意义(P0.05),且两组间差异无统计学意义(P0.05)。结论 -70℃冻存12个月内的参考品的细胞及体液免疫水平均未明显降低,可作为该参考品的长期保存条件。不同保存条件对疫苗免疫保护力的影响需进一步考察。     

富氧条件下煤粉气流的着火性能变化

利用一维火焰炉对不同富氧条件下的煤粉气流着火燃烧特性进行了研究,得到了富氧条件下煤粉气流的着火性能变化规律。研究结果表明:随着助燃气体氧浓度的提高,各煤样的着火温度均大幅下降,其中低挥发分煤种在着火方面对富氧条件的改善更为敏感,即富氧条件的改善可减弱煤种间着火性能方面的差异性;随着氧浓度的提高,煤粉气流的着火方式明显从均相着火向非均相着火转变,其中燃用褐煤时发生着火方式转变所对应的氧浓度为50%~60%,燃用烟煤时约为40%,燃用贫煤和无烟煤时都约为30%;对于烟煤和褐煤,随着氧浓度的提高,对应的最佳煤粉浓度值先增大后减小,而对于贫煤和无烟煤,由于其在整个实验氧浓度范围内基本上都以"非均相着火"为主,因此随着氧浓度的提高,对应的最佳煤粉浓度的值基本上呈缓慢下降的趋势。     

Durability of PBI adhesive bonded joints under various environmental conditions

Structural adhesives are finding increasing use in many applications. However, their utilization at elevated temperature has always been a challenge due to their low thermal and mechanical properties. However, in recent years, the development of high performance polymers have overcome the problem of using adhesive bonding at high temperature to some extent. Polybenizimidazole (PBI) is one such recently emerged high performance polymer with excellent thermal and mechanical properties. It has a tensile strength of 160 MPa and a glass transition temperature (T_g) of 425 °C. Due to its excellent thermal and mechanical properties, it has the potential to be used as an adhesive under various environmental conditions. In the present work, efforts are devoted to explore the potential of using PBI at high temperature and in hot-wet environmental conditions. M21 and DT120 epoxy based carbon fiber composite bonded joints were prepared and tested. Both M21/carbon composite and DT120/carbon composite have exhibited a reduction in joint strength of about 16% and 25% respectively after 1000 h of conditioning in a hot-wet environment. However, a reduction in lap shear strength of 52% and 56% is observed when composite bonded joints were tested at 80 °C.