Analysis on the Bioleaching Mechanism of Heavy Metal in Sludge by Composite Thiobacillus

The variation of heavy metal speciation during the bioleaching of sludge were carried out. By virtue of heavy metal speciation transformation pattern, the transformation mechanism of heavy metal speciation during the bioleaching could be judged indirectly. The test results show that the bioleaching process of Cu, Ni, Cd are mainly dominated by direct mechanism, the bioleaching process of Zn is mainly dominated by indirect mechanism, and bioleaching process of Cr, Pb are mainly dominated by combined mechanism, while the chemical principle between Cr and Pb are different.     

关于冻土地基的几点思考

随着寒区经济建设的不断发展,对于冻土的研究也引起更多学者的关注,本文主要分析了冻土力学特性,并简要介绍了冻土勘察特点。     

苏州古典园林“朴素生态观”理论与实践探索

人类追求"返璞归真"的生活状态,苏州古典园林可谓人类诗意栖居的典范,文章对其"朴素生态观"加以挖掘,旨在更好地推进苏州国家生态园林城市建设。     

时变多车型下的生鲜农产品配送路径优化模型

针对农业供应链的运输环节中生鲜农产品配送模型存在的速度恒定、碳排放计算方法单一的问题，本研究结合路网时变特征和新的多车型碳排放计算方法，提出了考虑配送距离、多车型碳排放量、货物损耗和车辆固定成本等4个优化目标的生鲜农产品配送路径优化模型；并根据模型特点提出了一种改进的双策略种群协同蚁群算法（Double-Strategies Co-Evolutionary Ant Colony System，DC-ACS ）。利用改进蚁群算法对Solomon数据集的C105算例进行了求解，在4个优化目标上分别取得最优解为937.94 km、4961.48元、4081.78元和7500.87元，证明了本研究提出的模型的有效性。在模型有效的基础上，通过试验结果证明，改进蚁群算法比基本蚁群算法在4个优化目标上的配送总成本平均降低幅度超过14%，证明改进蚁群算法更具有优越性。使用改进蚁群算法对集中、随机和混合3种不同分布的大规模算例进行求解，3种分布上分别求得最优总成本为19,939.53、24,095.00和24,397.58元。综上所述，所提模型和算法可以为冷链物流企业的城市配送路径决策提供良好的参考依据，对完善智慧农业供应链的配送路径优化模型和优化方法提供了新的思路，为企业进一步扩大规模提供了参考。     

Effect of genistein on the gene and protein expressions of CXCL–12 and EGR–1 in the rat ovary

The effect of genistein (GEN) on the gene expression level of stromal cell-derived factor-1/CXCL-12 and early growth response gene-1 was studied in ovarian tissue of young and initially ageing (early stages in the ageing process) female rats. Forty, young female Sprague Dawley (SD) rats of 2–3 months old (200 ±20 g) and forty, initially ageing female SD rats of 10–12 months (490 ± 20 g) old were selected. According to the weight, rats were divided into control group, low-dose group (L), medium-dose group (M) and a high-dose group (H) and were given 15, 30 and 60 mg/kg GEN respectively. The positive control (Oestrogen) group was given 0.5 mg/kg diethylstilbestrol. The treatment lasted for 30 days. The mRNA expression of C-X-C motif chemokine ligand 12 (CXCL-12) and early growth response factor-1 (EGR-1) was measured by real-time PCR, and protein expression of EGR-1 was detected by Western blot. When compared to the negative control group (NC), the ovary/body weight ratio in the young rats decreased in the GEN group, but the difference was not significant. Similarly, compared with NC, the ovary/body weight ratio in the initially ageing rats also decreased with the increase in GEN concentration, but the decrease was significant in M and H groups (p < .01). The administration of GEN enhanced both the gene and protein expression levels of CXCL-12 and EGR-1 in the ovary. Pearson's correlation analysis showed a synergistic effect between CXCL-12 and EGR-1. Thus, we conclude that the effect of GEN on CXCL-12 and EGR-1 in the initially ageing group was obvious than that in the younger group.     

不同种源红松主干挥发物对赤松梢斑螟危害的影响

为了研究相同生境条件下不同种源红松(Pinus koraiensis)挥发物对赤松梢斑螟(Dioryctria sylvestrel-la)危害的影响,调查了寒月、马鞍山、立林、宏伟和碧水5个种源的被害株率和幼虫钻蛀危害形成的凝脂团平均数,运用动态顶空取样法和GC-MS联用技术分析了不同种源红松健康主干释放挥发物的主要成分及相对含量.结果 表明:赤松梢斑螟的危害在这5个种源间存在显著性差异(P＜0.05).被害株率和平均凝脂团数最高的都是碧水种源,最低的均为立林种源,且差异显著(P＜0.05).红松受害程度与其主干的挥发物种类组成有一定的相关性.5个种源共发现27种主要挥发性化合物,其中烯萜类占23种.所有种源共有的挥发物为12种.寒月和马鞍山有22种挥发物,立林有21种,宏伟和碧水有17种.在被害株率和平均凝脂团数均差异显著的碧水和立林种源中,莰烯、罗勒烯、龙脑烯醛、乙酸龙脑酯、(-)-α-荜澄茄油烯、(+)-α-长叶蒎烯和(-)-α-古巴烯只存在于立林种源中;(-)-莰烯和萜品油烯则只存在于碧水种源中.相关分析结果表明,(1R)-(+)-α-蒎烯相对含量与被害株率(P=0.046)及平均凝脂团数(P=O.012)呈显著负相关关系(P＜0.05);(±)-β-水芹烯相对含量与被害株率(P=0.048＜0.05)呈显著正相关.     

基于神经网络和机器学习的白羽肉鸡体重估测算法

针对规模化肉鸡养殖生产中,传统肉鸡称重方法易造成应激问题,设计一种基于神经网络和机器视觉技术的非接触式肉鸡体重估测方法。应用深度相机采集白羽肉鸡的红外图像和深度信息,以目标识别算法YOLOv3和卷积网络分割算法FCN(Fully convolutional networks)为基础构建肉鸡区域提取模型,YOLOv3和FCN模型的查准率分别为98.1%和97.8%,查全率100%;结合肉鸡的深度信息,提取肉鸡投影面积等相关特征,构建多种回归算法,训练并调整优化肉鸡体重估测模型,ABR(Adaboost regressor)模型在测试集上达到最优的估测效果,该模型的决定系数R2为0.95,绝对误差为0.01～0.32kg。本研究的非接触式的肉鸡体重估测模型能较好的预测肉鸡体重,为实际生产环境中肉鸡自动称重提供了技术支持。     

桐油中脂肪酸组成特征图谱的构建和分析

为对桐油的品质评价和质量控制提供理论依据,本研究运用气相色谱法(GC)对23个不同家系的桐油脂肪酸组成进行数据采集,利用中药特征图谱相似度评价系统对其脂肪酸图谱进行分析,构建脂肪酸标准特征图谱并计算其相似度;采用办公软件对脂肪酸组成含量进行聚类分析与主成分分析.试验表明:从桐油样品中共检测出11种脂肪酸,各样品脂肪酸组成的相似度均达到90％以上,说明桐油样品脂肪酸组成信息是准确和可靠的;当聚类分析阈值取10.0时,桐油样品可分为3大类,主成分分析得出4个主要成分表达式,代表了桐油脂肪酸含量87.18％的信息,这些结果表明所建立的桐油的标准特征图谱能从化学成分的整体特征面代表桐油的脂肪酸组成信息,此研究结果可为桐油品质筛选及质量监控提供较好的理论基础,具有实际应用价值.