低物料残留软塑包装管形式研究

采用基于ANSYS的有限元法,分析了不同黏度的物料在变截面管中的流动速度分布,不同变截面数的软塑管对出口段物料流速的影响,以及不同管径比和不同管长比的变截面管中的物料流动速度分布。找出了控制残留量的主要因素和技术参数,以此对现存的软塑包装管提出了一些改良措施,为设计新的低物料残留的软塑包装管提供分析数据支持。

饲料熟化保持器产品概况与制标主要技术问题

目前饲料熟化保持器已经成为饲料加工中的重要设备,已在畜禽、水产、宠物饲料加工中体现出独特的优点和较好效益。文章介绍了国内外著名饲料机械公司生产的饲料熟化保持器产品的主要结构性能参数与特点,但目前国内外无该设备的国家和行业标准;同时提出了制定熟化保持器的标准需要进一步探讨的主要问题,包括产品名称、淀粉糊化度增加值、物料残留率、检修门尺寸、电加热热甲的安全性等。

浅谈长距离带式输送机与翻带装置

随着国民经济的发展,各行业对物料的输送提出了新的要求,带式输送机已不只是场内及车间与车间的输送设备,而成为可以与汽车运输相竞争的输送设备。翻带装置的设置有效地解决了长距离带式输送机运行中的诸多问题,对长距离带式输送机的运行起到了非常重要的作用。

粉体破拱排料设备选型及应用

针对料仓内出现空穴、搭桥、物料残留、结块等现象、对长期存放自然压实的无黏性易流化的粉末、热冷凝过程产生的流动性变差的粉末物料、轻微吸潮的粉料等,需选择不同的破拱措施,诸如气振动垫、流化下料锥、惯性振动排料器、水平搅拌破拱卸料机等。而针对潮湿和黏性或易板结的物料以及大的片状、块状或纤维状等特殊物料,应选择水平搅拌破拱卸料机、垂直搅拌转翼式破拱卸料机、多排螺旋破拱排料器等有针对性的破拱排料设备。

Effect of Dietary Olaquindox on the Growth of Large Yellow Croaker(Pseudosciaena crocea R.) and the Distribution of Its Residues in Fish Tissues

Olaquindox(OLA), one of quinoxaline-N, N-dioxides, has been put under ban. However it was used as a medicinal feed additive early; it promotes the growth of livestock and prevents them from dysentery and bacterial enteritis. In this study, we evaluated the effect of dietary OLA on the growth of large yellow croaker(Pseudosciaena crocea R.) and the histological distribution of OLA and its metabolite 3-methyl-quinoxaline-2-carboxylic acid(MQCA) in fish tissues. Four diets containing 0(control), 42.5, 89.5 and 277.2 mg kg-1 OLA, respectively, were formulated and tested, 3 cages(1.0 m × 1.0 m × 1.5 m) each diet and 100 juveniles(9.75 ± 0.35 g) each cage. The fish were fed to satiation twice a day at 05:00 am and 17:00 pm for 8 weeks. The survival rate of fish fed the diet containing 42.5 and 89.5 mg kg-1 OLA was significantly higher than that of fish fed the diet containing 0 and 277.2 mg kg-1 OLA(P < 0.05), while the weight gain rate of fish fed the diet containing 42.5 and 89.5 mg kg-1 OLA was significantly higher than that of fish fed the diet without OLA(control)(P<0.05), but similar to that of fish fed the diet with 277.2 mg kg-1 OLA. Fish fed the diet with 277.2 mg kg-1 OLA had the highest content of OLA and MQCA in liver(3.44 and 0.39 mg kg-1, respectively), skin(0.46 and 0.09 mg kg-1, respectively) and muscle(0.24 and 0.06 mg kg-1, respectively). In average, fish fed the diet containing OLA had the highest content of OLA and MQCA in liver which was followed by skin and muscle(P < 0.05), whereas OLA and MQCA were not detectable in control. Our findings demonstrated that OLA and MQCA accumulated in large yellow croaker when it was fed with the diet containing OLA, thus imposing a potential safety risk to human health.

Species Transformation of Trace Elements and Their Distribution Prediction in Dyestuff Residue Incineration

The release of heavy metals from the combustion of hazardous wastes is an environmental issue of in-creasing concern.The species transformation characteristics of toxic heavy metals and their distribution are consid-ered to be a complex problem of mechanism.The behavior of hazardous dyestuff residue is investigated in a tubular furnace under the general condition of hazardous waste pyrolysis and gasfication.Data interpretation has been aided by parallel theoretical study based on a thermodynamic equilibrium model based on the principle of Gibbs free en-ergy minimization.The results show that Ni,Zn,Mn,and Cr are more enriched in dyestuff residue incineration than other heavy metals(Hg,As,and Se)subjected to volatilization.The thermodynamic model calculation is used for explaining the experiment data at 800℃ and analyzing species transformation of heavy metals.These results of species transformation are used to predict the distribution and emission characteristics of trace elements.Although most trace element predictions are validated by the measurements,cautions are in order due to the complexity of incineration systems.

离子色谱-直接电导法测定坎地沙坦酯中叠氮化钠和四丁基溴化铵残留

目的:建立离子色谱-直接电导法测定坎地沙坦酯中叠氮化钠和四丁基溴化铵残留。方法:坎地沙坦酯经二氯甲烷溶解后加水进行萃取,水相经C18固相萃取小柱萃取后直接进样。采用氢氧化钾溶液为淋洗液进行梯度洗脱,以Ionpac AS18(4 mm×250 mm)色谱柱及相应的Ionpac AG18(4 mm×50 mm)保护柱进行分离,流速为1.0 mL·min^-1,ASRS 500-4 mm阴离子抑制器和电导检测器抑制并直接检测,抑制电流99 mA,柱温35℃,进样体积200μL。结果:叠氮根离子、溴离子与其他成分的分离度良好,叠氮根质量浓度在2.33~932 ng·mL^-1范围内线性关系良好(r=0.999 6),检测下限(S/N=3)为0.699 ng·mL^-1,定量下限(S/N=10)为2.33 ng·mL^-1;溴离子质量浓度在4.8~240 ng·mL^-1范围内线性关系良好(r=0.999 5),检测下限(S/N=3)为1.44 ng·mL^-1,定量下限(S/N=10)为4.8 ng·mL^-1。共进行9批样品检测,其中4批样品含有叠氮化钠或四丁基溴化铵。结论:本方法操作简单,灵敏度高,重复性好,可用于坎地沙坦酯中叠氮化钠和四丁基溴化铵残留的检测。