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H. Harry Szmant Deena D. Chundury 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1981,31(1):205-212
A 92–95% conversion of high fructose corn syrup (HFCS) or crystalline D -fructose to 5-chloromethylfurfuraldehyde (CMF) was achieved using 300 mol% of concentrated hydrochloric acid in chlorobenzene, under a nitrogen atmosphere, a reaction temperature of 75°C and a reaction time of 1–2 h. Constant high-speed stirring was essential for high yields and purity of CMF. Inferior yields of CMF were obtained from glucose and starch. Saccharine, phenyl sulphone and thiuronium derivatives were prepared and characterised. The use of surfactants did not improve the yields of CMF. 相似文献
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David W. Koren Zdravko Duvnjak 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1990,47(2):117-125
Saccharomyces cerevisiae ATCC 36859 preferentially consumes glucose from glucose–fructose mixtures. Synthetic media and complex media containing high fructose corn syrup supplemented with Jerusalem artichoke juice were used for the production of pure fructose syrup by the conversion of glucose to ethanol. Fructose was not converted in these processes. Increasing the concentration of Jerusalem artichoke juice increased the yields of ethanol and biomass and decreased the process time. A similar effect was obtained at a low juice concentration when a larger amount of biomass was used for the inoculum. The product from this process contained only fructose and ethanol. Use of food-grade materials results in a pure fructose syrup that is suitable for human consumption. 相似文献
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《Journal of Industrial and Engineering Chemistry》2013,19(4):1106-1111
5-Hydroxymethyl-2-furfural (HMF) was prepared with high fructose corn syrup (HFCS) manufactured directly from industry. Equipped industrial process and cheaper availability considered HFCS-90 as a competitive starter for production of HMF. Readily evaporable solvent, 1,4-dioxane was found as a promising reaction media from the screening of various solvents and readily available cation exchange resin, Amberlyst-15 was used as a solid acid catalyst. Parametric variation studies including amount of catalyst, concentration of HFCS-90, and reaction temperature were performed to achieve a maximum HMF yield of 80% at 100 °C within 3 h. In particular, use of readily evaporable solvent and heterogeneous catalyst allowed highly practical purification of HMF, which still remains as a major obstacle to the commercialization of HMF. With filtration, evaporation, and extraction, HMF was simply isolated in 72% yield and 1H NMR spectra of the isolated HMF confirmed that its purity was sufficient for use in next step of reactions. In addition, all solvents could be recycled with distillation and catalyst was reused up to 5 cycles without a significant loss of activity. 相似文献
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ABSTRACT: BACKGROUND: The replacement of sucrose with HFCS in food products has been suggested as playing a role in the development of obesity as a public health issue. The objective of this study was to examine the effects of four equally hypocaloric diets containing different levels of sucrose or high fructose corn syrup (HFCS). METHODS: This was a randomized, prospective, double blind trial, with overweight/obese participants measured for body composition and blood chemistry before and after the completion of 12 weeks following a hypocaloric diet. The average caloric deficit achieved on the hypocaloric diets was 309 kcal. RESULTS: Reductions were observed in all measures of adiposity including body mass, BMI, % body fat, waist circumference and fat mass for all four hypocaloric groups, as well as reductions in exercise only group for body mass, BMI and waist circumference. CONCLUSIONS: Similar decreases in weight and indices of adiposity are observed when overweight or obese individuals are fed hypocaloric diets containing levels of sucrose or high fructose corn syrup typically consumed by adults in the United States. 相似文献
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玉米淀粉胶粘剂的研制 总被引:3,自引:1,他引:3
采用高锰酸钾作氧化剂,经氧化,糊化,交联等步骤,可于室制备出一种粘度适中,粘性,流动性及稳定性好的玉米淀粉胶粘剂。通过实验,确定了高锰酸钾,氢氧化钠,硼砂的最佳用量分别为0.8-1.6,10,0.5-1.0份(100份淀粉中加入量),水与淀粉的最佳质量比为6:1-6.5:1。 相似文献
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研究以玉米芯为原料,十二烷基本磺酸钠为改性剂制取玉米芯活性炭的最佳工艺条件。通过单因素实验和正交试验得出玉米芯活性炭的最佳条件是:振荡温度为35℃,振荡时间为3h,玉米芯与十二烷基本磺酸钠的料液比为1:6,十二烷基本磺酸钠质量分数为9%,各因素的影响顺序为振荡温度料液比LAS质量分数振荡时间,并对普通玉米芯及市售活性炭吸附性能的对比进行了一定的探讨。 相似文献
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离子液体中果糖脱水制5-羟甲基糠醛 总被引:3,自引:0,他引:3
以阳离子相同(1-丁基、3-甲基咪唑、[Bmim] )、阴离子不同(Cl-、Br-、[CF3COO]-、[BF4]-、[H2SO4]-和[H2PO4]-)的6种离子液体为溶剂和催化剂,研究反应时间(15~180 min)、反应温度(80~120℃)和离子液体种类对果糖脱水制5-羟甲基糠醛(5-HMF)过程的影响.结果表明,随着时间延长和温度升高,果糖转化率和5-HNF产率增大,但是长时间和高温会降低反应选择性;L酸性的离子液体比B酸性的有利于催化果糖脱水,Cl-离子的存在可抑制分子间缩聚,提高反应选择性.以[Bmim]Cl离子液体为溶剂和催化剂,在120℃和120min条件下,果糖转化率达94.4%,5-HNF产率为70.8%. 相似文献
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Philip E. Barker George Ganetsos 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(4):217-228
A semi-continuous counter current chromatographic refiner, developed in this department, was used to produce high fructose syrup from an industrial barley syrup containing 42% fructose, 52% glucose and 6% maltose and oligosaccharides. The chromatographic refiner consisted of twelve 5.4 cm i.d. columns, each packed to a height of 65.5 cm with KORELA VO7C calcium charged resin, with a particle size range 150–300 μm. At a throughput of 32.1 kg sugar solids/m3 resin/h, the fructose rich product obtained was 95% pure and had a concentration of 11.3% w/v, while the glucose rich product contained only 4.5% fructose and had a concentration of 22.56% w/v. 相似文献
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采用浸渍法制备氧化铌负载氧化钨固体酸催化剂,用XRD、EDS、TEM、NH3-TPD、Py-IR、BET、BJH对催化剂的结构、组分、形貌、酸性、比表面积及孔径等进行表征;并将其用于催化果糖转化为5-羟甲基糠醛( HMF) 反应,对氧化钨负载量、反应时间、反应温度、催化剂用量等影响因素进行考察。结果表明,氧化钨负载量对催化剂结构、酸性以及催化活性均有影响:随着WO3负载量的增加,氧化钨分子从表面分散的非晶态WO3转变为结晶WO3,且Nb2O5上适量的WO3产生大量强酸位点,使催化剂的Brønsted酸含量增加,从而使果糖的转化率得到提高;但结晶WO3却不利于HMF的生成。当氧化钨的负载量为5%时 ,在催化剂加入量为100mg,170 ℃条件下反应1 h,HMF选择性 较高为85.4%,收率可达49.6%。 相似文献
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Production enhancement of 5‐hydroxymethyl furfural from fructose via mechanical stirring control and high‐fructose solution addition 下载免费PDF全文
Nan Jiang Wei Qi Renliang Huang Mengfan Wang Rongxin Su Zhimin He 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2014,89(1):56-64
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High selective production of 5-hydroymethylfurfural from fructose by a solid heteropolyacid catalyst 总被引:1,自引:0,他引:1
A clean, facile, economical, and environmental friendly method for converting fructose into 5-hydroymethylfurfural (HMF) has been developed, in the presence of a solid heteropolyacid Cs2.5H0.5PW12O40 catalyst in a biphasic system. A 5-HMF yield of 74.0% and a higher selectivity of 94.7% were obtained in 60 min at 388 K. More importance is that this catalyst is tolerant to high concentration feedstocks (50 wt.% fructose) and it can be recycled. 相似文献
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Feeding responses of eastern spruce budworm larvae to sucrose and other carbohydrates 总被引:1,自引:0,他引:1
Spruce budworm larvae reared on an artificial diet were tested for preference of twelve carbohydrates over a water control. A strong preference for sucrose was seen, followed by fructose, inositol, and glucose. Male and female larvae do not differ in their responses to sucrose. The behavioral threshold for sucrose is at 10–4 to 10–3 M, with a peak response in the range of 0.01 to 0.05 M sucrose.
Choristoneura fumiferana (Clem.) (Lepidoptera: Tortricidae).Work leading to this publication was funded in part by a USDA Forest Service sponsored program entitled Canada/United States Spruce Budworms Program (grant 23–352), and in part by the National Sciences and Engineering Council of Canada (operating grant A9723), and in part by the Whitehall Foundation. 相似文献