酒糟黄姑鱼生产加工过程HACCP计划的建立

对酒糟黄姑鱼生产加工过程进行危害分析,确定了加工前原料验收、辅料验收、解剖、干制、发酵储藏5个关键控制点,并制订了HACCP计划表,构建了酒糟黄姑鱼的HACCP管理体系模式,确保产品的质量安全。     

不同保鲜处理对即食菠萝质量变化的影响

新鲜菠萝经机械削皮、去果眼、切分和清洗后用４种保鲜方法处理,分虽在４～５和１４～１５℃下贮存,并测定菠萝的呼吸强度、可溶性固形物和可滴定酸含量,菌落总数、大肠菌群、霉菌和酵母及致病菌,进同时行色、香、味和质地等的感官评定。试验结果表明,含０．２～０．４ｇ／１００ｍＬ食盐、８～１２ｇ／１００ｍＬ蔗糖和０．３～０．５ｇ／１００ｍＬ柠檬酸的溶液于６６～７５℃处理３～６ｍｉｎ能使菠萝的生命活动维持在较低水平,保持菠萝原有的新鲜状况,且产品的各项微生物指标均符合即食产品的卫生要求。产品贮存在１４～１５℃下７ｄ或４～４℃下１４ｄ均无明显的质量变化。据此提出了即食菠萝产品的质量指标和要求。     

New alkamides from maca (Lepidium meyenii)

Maca (Lepidium meyenii) has been used as a food in Peru for thousands of years. More recently a wide array of commercial maca products have gained popularity as dietary supplements, with claims of anabolic and aphrodisiac effects, although the biologically active principles are not fully known. In an earlier chemical investigation, two new alkamides and a novel fatty acid, as well as the N-hydroxypyridine derivative, macaridine, were isolated from L. meyenii. Further examination has led to the isolation of five additional new alkamides, namely, N-benzyl-9-oxo-12Z-octadecenamide (1), N-benzyl-9-oxo-12Z,15Z-octadecadienamide (2), N-benzyl-13-oxo-9E,11E-octadecadienamide (3), N-benzyl-15Z-tetracosenamide (4), and N-(m-methoxybenzyl)hexadecanamide (5). Their structures were established by spectrometric and spectroscopic methods including ESI-HRMS, EI-MS, (1)H, (13)C, and 2D NMR, as well as (1)H-(15)N 2D HMBC experiments. In addition, the identity of N-benzyl-15Z-tetracosenamide (4) was confirmed by synthesis. These compounds have been found from only L. meyenii and could be used as markers for authentication and standardization.     

生产建设项目弃渣(土)场水土流失特征与防治措施

生产建设项目弃渣场种类繁多,弃渣成分、结构复杂,各类弃渣场的侵蚀形式、机制不尽相同,不易实施适宜的水土保持措施,致使弃渣场水土流失十分严重。通过介绍弃渣场存在的各类土壤侵蚀型式、归纳土壤侵蚀类型、分析岩土侵蚀特点,指出影响弃渣场土壤侵蚀的主要因素有排弃方式、组成物质、坡面以及堆积时间等。结合保证弃渣场安全稳定、恢复土地生产力的弃渣场水土流失防治目标,分析现有水土保持措施特点,提出健全弃渣场水土流失防治措施体系的建议,为弃渣场的水土流失防治提供科学依据。     

Differential expression of peroxisome proliferator-activated receptors alpha and gamma gene in various chicken tissues

The peroxisome proliferator-activated receptors (PPARs) are the members of superfamily of nuclear hormone receptors. A great number of studies in rodent and human have shown that PPARs were involved in the lipids metabolism. The goal of the current study was to investigate the expression pattern of PPAR genes in various tissues of chicken. The tissue samples (heart, liver, spleen, lung, kidney, stomach, intestine, brain, breast muscle and adipose) were collected from six Arber Acres broilers (8 weeks old, male and female birds are half and half). Semi-quantitative RT-PCR and Northern blot were used to characterize the expression of PPAR-alpha and PPAR-gamma genes in the above tissues. By semi-quantitative RT-PCR, the results showed the expression level of PPAR-alpha gene was higher in brain, lung, kidney, heart and intestine, medium in stomach, liver and adipose than in spleen, and it did not express in breast muscle. The expression level of PPAR-gamma gene was higher in adipose, medium in brain and kidney than in spleen, heart, lung, stomach and intestine, but it did not express in liver and breast muscle. Northern blot results showed that PPAR-alpha gene expressed in heart, liver, kidney and stomach, and the intensity of hybridization signal was the stronger in liver and kidney than in other tissues, however, PPAR-gamma gene only expressed in adipose and kidney tissues. The results of this study showed the profile of PPAR gene expression in the chicken was similar to that in rodent, human and pig. However the expression profile of chicken also have its own specific trait, i.e. compared with mammals, PPAR-alpha gene can not be detected in skeletal muscle and PPAR-gamma gene can be stronger expressed in kidney tissues. This work will provide some basic data for the PPAR genes expression and lipids metabolism of birds.     

奶牛主要植物性蛋白质饲料蛋白质和纤维物质瘤胃降解率的研究

选用3头安装永久性瘤胃瘘管的健康荷斯坦产奶牛为试验动物,选取8种北方地区奶牛常用蛋白质饲料原料为试验样品,每个样品设3个重复,用尼龙袋法分别测定各个样品的粗蛋白质(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)在瘤胃内的动态降解率和有效降解率。结果表明:(1)所选8种蛋白质饲料原料中葵花粕的粗蛋白质(CP)有效降解率均高于其他粗饲料,达到61.17%以上,酒精粕的粗蛋白质(CP)有效降解率最低,仅为19.03%。(2)在饲喂基础上,玉米蛋白粉所含的瘤胃降解蛋白质(RDP)的比例最高,达到30.99%以上,而酒精粕所含的比例最低,仅为5.52%。(3)豆粕所含的中性洗涤纤维(NDF)的有效降解率最高,达到50.74%以上,而菜籽粕的最低,仅为11.06%。(4)玉米蛋白粉所含的酸性洗涤纤维(ADF)的有效降解率最高,达到59.23%以上,而酒精粕的最低,仅为11.27%。     

基于Solidworks的复合式小麦匀播机的结构设计

根据小麦播种的特点,提出一种复合式小麦匀播的新型结构机械。对匀播机进行了虚拟设计,应用Solidworks对匀播机进行模块化虚拟建模,包括悬挂机构、旋耕机构、施肥机构、播种机构、匀播机构、镇压机构和松土装置;通过虚拟样机的设计,使得样机的研发节省了时间,降低了成本。样机的田间试验结果表明:该设备具有结构简单、工作可靠、维护方便的特点。     

Effects of the dietary protein to energy ratio on growth,feed utilization and body composition in Macrobrachium nipponense

Oriental river prawn (Macrobrachium nipponense) has been widely cultured in Asian countries. However, its nutritional studies are very limited. In the present 8‐week study, we investigated the effects of dietary protein to energy ratio (P/E ratio) on the growth, feed utilization and body composition in juvenile M. nipponense (initial weight 0.302 ±0.03 g). Two‐factor experiment was designed and nine semi‐purified diets were formulated to contain three lipid levels (20, 80 and 140 g kg^?1) and three protein levels (330, 380 and 430 g kg^?1), producing P/E ratios from 16.5 to 23.4 mg KJ^?1 protein. The results indicated that the growth, survival rate and protein efficiency were dose dependently improved by the increased dietary lipid, but not dietary protein content. Increased dietary lipid content and/or protein content increased lipid accumulation in whole body, hepatopancreas and muscle, but did not change the feed intake and hepatopancreas weight. In conclusion, our present study indicated that M. nipponense is a species with relatively high‐energy requirement. It could utilize dietary lipid content up to 140 g kg^?1, while the dietary protein with more than 330 g kg^?1 would not promote growth and protein efficiency. Taken together, 330 g kg^?1 dietary protein and 140 g kg^?1 dietary lipid level with P/E ratio 16.49 could be optimum for M. nipponense.     

定向刨花板加固腹板开洞竹木工字梁力学性能研究

为研究定向刨花板(oriented strand board,OSB)加固腹板开洞的竹木工字梁的力学性能,揭示其受力破坏机理。以孔径与腹板高度的比值(d/hw)和补强板型为参数,制作并测试了42根竹木工字梁,考察测试过程中的破坏形态、弯曲变形性能,分析各因素对工字梁力学性能的影响规律。结果表明,当孔径较小(d/hw≤25%)时,试件的破坏形态以翼缘内OSB层裂和腹板剪切破坏为主,孔洞对开洞梁承载力和刚度的影响较小,可忽略不计。当孔径较大(d/hw25%)时,破坏形态以洞口周边受拉和受压破坏为主,随着孔洞直径d增加,孔洞的不利影响愈发明显,开洞梁的承载能力呈下降趋势,但对梁的刚度影响较小。OSB补强板能有效约束孔角裂缝开展,加固后的开洞梁的开裂荷载、正常使用极限状态荷载和承载能力极限状态荷载较未加固开洞梁明显提高,平均提高52.9%、12.1%和28.2%。但OSB补强板对开洞梁抗弯刚度的改善作用不明显,平均提高仅为11.5%。承载力和刚度的提高幅度与补强板类型密切相关,其中,套环定向刨花板(collar oriented strand board,C-OSB)增强效果最好、双U型定向刨花板(two U shaped oriented strand board,TU-OSB)次之,U型定向刨花板(U shaped oriented strand board,U-OSB)最差。C-OSB适合于管道施工前对开洞梁进行加固,而U-OSB和TU-OSB适合加固d/hw不大于75%的开洞梁。粘贴OSB加固开洞竹木工字梁是一种有效的加固方法。     

玉米秸秆整株还田对土壤水肥及冬小麦生长发育的影响

介绍在小麦，玉米一年两熟条件下，玉米秸秆整株还田对土壤水肥及小麦生长发育的影响。重点介绍玉米整株还田技术，所需配套机具有操作工艺，技术要点和3年的实验结果。研究结果表明：整株还田，秸直经过一年的腐解，腐解率达90％以上，玉米整珠还田耕深20cm，秸杆在土壤8cm深度以下秸秆覆盖率达95％以下，能够保证冬小麦播种质量，小麦播种出苗后基本苗蘖测定分别比粉碎还田（对照）增加23株和0．2个，小麦生育期干物质和千粒重分别增加8．95％和1．33％，小麦产量提高3．18％。