木质复合板优良复合工艺的初步研究

采用正交试验法，探讨了热压温度，热压压力，热压时间及施胶量等对单板覆面的刨花板性能的影响，确定了优良复合工艺。研究结果表明，制造的木质复合板各项性能大大高于普通刨花板，表面质量明显改善，特别是静曲强度是普通刨花板的２．０－２．５倍，提高木材综合利用率３０％－３５％，具有可观效益。     

千岛湖地区天然马尾松林高产结构模式的探讨

应用数量化方法Ⅰ,研究了千岛湖天然马尾松林的林分结构因子和林分蓄积量之间的定量关系,得到以下结论:在林分蓄积量中,林分每公顷林木株数的作用占主导地位,相对得分为55.04;其次是林分平均直径。20～30年生天然马尾松林的高产结构最佳模式是:林分密度1650～1950株/hm~2,平均胸径22～26cm,郁闭度0.8以上的林分,其蓄积量的估计值为222.16m~2/hm~2。本文还给出了天然马尾松林蓄积量的估计模型。     

聚晶金刚石—硬质合金复合片木工刀具的研制及其分析

以金属钴(Co)为主要成分的粘结剂,在高温高压下成功地将金刚石微粉与YG15硬质合金合成为聚晶金刚石—硬质合金复合片的超硬材料。经机械性能测试表明:当金刚石含量在85％左右时,聚晶复合片的抗弯强度较理想,适宜作木工刀具。同时,采用HL315硬钎焊解决了与45号钢制刀体的焊接问题。其刃部采用电火花粗磨及陶瓷基金刚石砂轮精磨,满足了聚晶复合片刀头的设计要求。于同类硬质合金刀具相比,其耐用度高20多倍,加工刨花板的刀具损耗费约下降37％,加工的表面质量优良。     

大麻籽粕营养成分研究

 为了开发利用大麻籽粕，探讨其作为蛋白质饲料的可能性和可行性，首次按照国标方法对其进行了化学成分和氨基酸成分测定，计算了氨基酸化学分数。结果：大麻籽粕的粗蛋白质、粗脂肪、粗纤维、粗灰分分别为35.2%,0.5%,24.4%和8.7%，富含精氨酸、甘氨酸、丝氨酸和亮氨酸，蛋氨酸含量较低，蛋氨酸、胱氨酸和赖氨酸分别是大麻籽粕的第一、第二和第三限制性氨基酸，表明大麻籽粕可作为蛋白质饲料资源部分替代豆粕，但要在大麻籽的脱壳、提油工艺上注意提高粗脂肪含量、降低粗纤维含量，并注意氨基酸的平衡。     

手工拉面评分指标与面筋数量和质量的关系

手工拉面是一种特殊的面条加工形式。本研究选用目前正在甘肃河西大面积推广种植的9个小麦品种及21个新近育成的品系，测定其干、温面筋含量、面筋指数以及手工拉面各项评分指标，并通过相关分析、通径分析及多无线性回归分析，对拉面面条各项评分指标与面筋数量、质量间的关系进行了研究。结果表明，面筋数量和质量对面条各评分指标都具有直接或间接作用，这些作用的结果，使得面筋数量和质量对面条总评分的影响达到了极显著的水平。所得8个回归方程的可靠程度较高，模型合理，实用性强，可用于直接预测拉面各评分指标及总评分，是评价拉面品质的一种简单有效的方法。     

Nutritional properties of nonrice crops in the Asian Rice Farming Systems Network

Six legume crops and three cereal crops in the Asian Rice Farming Systems Network were compared with IR58 brown rice in terms of dry matter, energy and protein yields per hectare. Sorghum was closest to brown rice in dry matter and energy yield but soybean had the highest protein yield. Peanut and soybean had higher crude fat than the other crops which accounted for their high energy content and yield among the legumes. Amino acid analysis showed cowpea, mungbean, pigeonpea, bushsitao, and soybean protein as limiting in sulfur amino acids (cysteine + methionine). Peanut protein was limiting in either lysine or tryptophan + threonine. Corn, sorghum and wheat proteins were limiting in lysine.     

Interactions between ice storage time, collagen composition, gaping and textural properties in farmed salmon muscle harvested at different times of the year

Atlantic salmon were sampled in June, September and February of the consecutive year and were stored on ice for up to 14 days in order to test the effect of harvest time and subsequent ice storage on meat quality. Texture and gaping frequency were analysed and were related to colour, protein degradation, collagen solubility, collagen types and final pH as well as lipid oxidation in the fillets to test possible interactions between harvest time and quality degradation during storage. In February, the connective tissue contained more soluble collagen and less insoluble collagen, as well as more of both types I and V collagen, than in the samples collected in June. During ice storage, fish became softer with a concomitant increase in the number of fish displaying very high gaping. pH increased during ice storage and fillet colour became lighter and redder, while yellowness changed in the fattier fillets upon ice storage. Ice storage resulted in changes in pepsin-soluble collagen (PSC) depending on harvest time as did both types I and V collagen. The softer the fish, the higher the gaping score and the more insoluble collagen, the less gaping occurred.     

Subclinical ketosis in dairy cows: prevalence and risk factors in grazing production system

The purpose of this study was to estimate the prevalence of Subclinical ketosis (SCK) between 4 and 19 days in milk (DIM) in a grazing production system and investigate the importance of potential risk factors for SCK. This cross‐sectional study was conducted in dairy cows (n = 107), which had more of two parities. The concentration of β‐hydroxybutyric (BHB) in blood was quantified through a hand‐held meter. Potential risk factors evaluated were calving interval (CI), milk yield in previous lactation, metritis, dystocia, calf sex (male), parity (≤3 vs. ≥4) and pre‐partum body condition score (BCS ≤ 3.5 vs. ≥3.75). Prevalence of SCK was 10.3% (95% CI 4.7–15) between 4 and 19 DIM. Risk factors identified were the occurrence of both metritis and pre‐partum BCS ≥ 3.75. Cows with metritis had 4.9 (95% CI 1.17–20.98) times more risk of developing SCK than cows without metritis. And the cows with pre‐partum BCS ≥ 3.75 had 5.25 (95% CI 1.32–21.11) times more risk of developing SCK than cows with pre‐partum BCS ≤ 3.5. Metritis could induce a lower feed intake and promote the development of SCK. High pre‐partum BCS could induce a greater mobilization of body reserves altering liver function and aggravating post‐partum NEB. The results are indicative of the expected prevalence of SCK in grazing production system. Factors associated could help to identify cattle at risk of SCK and improve the management of strategies to limit the effects.