Flow in planar graphs with vertex capacities

Max-flow in planar graphs has always been studied with the assumption that there are capacities only on the edges. Here we consider a more general version of the problem when the vertices as well as edges have capacity constraints. In the context of general graphs considering only edge capacities is not restrictive, since the vertex-capacity problem can be reduced to the edge-capacity problem. However, in the case of planar graphs this reduction does not maintainplanarity and cannot be used. We study different versions of the planar flow problem (all of which have been extensively investigated in the context of edge capacities).A preliminary version of this paper appeared in theProceedings of the First Integer Programming and Combinatorial Optimization Conference, Waterloo, Canada, May 1990, pp. 367–383. Samir Khuller is currently supported by NSF Grant CCR-8906949. Part of this research was done while he was visiting the IBM Thomas J. Watson Research Center and was supported by an IBM Graduate Fellowship at Cornell University. Joseph Naor's work was supported by Contract ONR N00014-88-K-0166 while he was a post-doctoral fellow in the Department of Computer Science at Stanford University.     

某工程基础下沉变形的原因分析与加固措施

对山东省某牛皮箱纸板车间地基基础沉降变形事故进行了原因分析,认为其主要原因为地基中局部存在湿陷性黄土和新近填土层,对地基变形和承载力有不利影响.在此基础上,采用静压灌浆的方法加固地基,使原地基土与灌浆充填后的凝结体形成复合地基,共同承受荷载.随着灌浆后浆液凝结体龄期的延长,地基压力得以进一步调整和恢复,基础沉降速率减小,完全达到加固、稳定的目的.     

Phytochemical Characterization of Chinese Bayberry (Myrica rubra Sieb. et Zucc.) of 17 Cultivars and Their Antioxidant Properties

In order to fully understand the variations of fruit quality-related phytochemical composition in Chinese bayberry (Myrica rubra Sieb. et Zucc.), mature fruit of 17 cultivars from Zhejiang and Jiangsu provinces was used for the investigation of fruit quality attributes, including fruit color, soluble sugars, organic acids, total phenolics, flavonoids, antioxidant capacity, etc. Sucrose was the main soluble sugar, while citric acid was the main organic acid in bayberry fruit. The content of total phenolics and total flavonoids were positively correlated with 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) antioxidant activity and 2,2ʹ-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activity. Five anthocyanidins, i.e., delphinidin–hexoside (Dp–Hex), cyanidin-3–O-galactoside (C-3–Gal), cyanidin-3–O-glucoside (C-3–Glu), pelargonidin-3–O-glucoside (Pg-3–Glu) and peonidin-3-O-glucoside (Pn-3–Glu), and seven flavonols compounds, i.e., myricetin-3-O-rhamnoside (M-3–Rha), myricetin deoxyhexoside–gallate (M-DH–G), quercetin-3-O-galactoside (Q-3–Gal), quercetin-3–O-glucoside (Q-3–Glu), quercetin-3–O-rhamnoside (Q-3–Rha), kaempferol-3–O-galactoside (K-3–Gal) and kaempferol-3–O-glucoside (K-3–Glu), were identified and characterized among the cultivars. The significant differences in phytochemical compositions among cultivars reflect the diversity in bayberry germplasm, and cultivars of good flavor and/or rich in various health-promoting phytochemicals are good candidates for future genetic breeding of bayberry fruit of high quality. In conclusion, our results may provide important information for further breeding or industrial utilization of different bayberry resources.     

金银花提取液抗氧化酶活性与清除自由基能力的研究

为研究金银花不同采收期和不同部位提取液膜保护酶的活性与清除自由基的能力,采用生物化学分析法测定了不同采集期金银花花蕾、叶片和枝条膜保护酶活性,结果显示,SOD、POD和CAT活性从4月开始平稳上升,6月上旬前后达到最高值。叶片的上述指标最高,枝条最低。对自由基的清除能力也呈平稳上升趋势。金银花花蕾对超氧自由基和羟自由基的清除效应最高,花蕾和叶片对过氧化氢清除效应相当,枝条的最低。几种膜保护酶活性之间均呈较显著的正相关,当膜保护酶活性增强时,清除自由基的能力也随之提高,可能是它们的协调作用使金银花有较强的清除自由基的能力。     

谷氨酰胺转氨酶对猪肉糜失水率和硬度影响的研究

研究了谷氨酰胺转氨酶对猪肉糜保水性及对猪肉糜糕弹性的影响。结果表明最佳作用添加量为0.45%、最佳作用温度为35℃、最佳作用时间为2.0h;辅料大豆蛋白GsNa、大豆蛋白EGP和大豆蛋白HTP对谷氨酰胺转氨酶作用影响结果表明添加4%的大豆蛋白GsNa和添加0.1%的大豆蛋白EGP能显著改善猪肉糜的保水性及猪肉糜糕的弹性,而大豆蛋白HTP对其影响则不明显。     

A new formalism for representation of heat capacities of metals

The applicability of a function involving geometrical progression of temperature in interpreting the heat capacities of metals has been studied. The constants of the function have been described in terms of vibrational, electronic and magnetic contributions to heat capacities. The equation may be useful in representing heat capacity of metals.     

Stability constants and complexation capacities of complexes formed between heavy metals and extracellular polymers from activated sludge

Conditional stability constants and complexation capacities of extracellular polymers extracted from activated sludge with copper, nickel, cadmium and cobalt have been determined at high and low free metal concentrations using gel complexometry. The results compare favourably with those for other bacterial extracellular polymers, but less well with those for competing metal-binding ligands present in sewage. The affinity of extracellular polymers for metals has been discussed in terms of their contribution to metal removal during the biological phase of wastewater treatment.     

西安地区用静力触探预估钻孔灌注桩极限承载力的研究

根据西安地区某些工程中的钻孔灌注桩试桩资料以及勘察报告,分析了由静力触探法预估钻孔灌注桩极限承载力标准值时应考虑的因素,通过对该地区的分析,建立由静力触探法预估钻孔灌注桩的竖向极限承载力标准值的经验公式。工程验证结果表明,计算值与实测值比较吻合。     

An Experimental Investigation into the Feed Rate Capacity of Rotary Valve and Blow Tank Feeders

Industry widely uses rotary valves and blow tanks for the pneumatic conveying of products, each having their pros and cons depending on the specific application. This article shows the differing results obtained when low-velocity conveying a product through a common pipeline using both a drop-through rotary valve and a bottom-discharge blow tank feeder. A number of issues arise in the rotary valve system, the main one being rotary valve air leakage. A blow tank system, on the other hand, does not leak, as it is an enclosed system. The experimental results show dramatic differences in product throughput. Further exploration leads to a novel modification being made to the rotary valve system in an attempt to increase its capacity. The result of this modification shows a slight increase in output tonnage, but still significantly less than that obtained from the blow tank.     

Antioxidant capacities of α-tocopherol,trolox, ascorbic acid,and ascorbyl palmitate in riboflavin photosensitized oil-in-water emulsions

Antioxidant capacities of α-tocopherol, trolox, ascorbic acid, and ascorbyl palmitate at 0.01, 0.1, and 1.0 mM in riboflavin photosensitized oil-in-water (O/W) emulsions were determined using headspace oxygen depletion, lipid hydroperoxide, and headspace volatile analyses. After 32 h visible light irradiation, headspace oxygen in O/W emulsions without adding antioxidants, with 1.0 mM α-tocopherol, trolox, ascorbic acid, and ascorbyl palmitate decreased to 18.50%, 18.85%, 16.01%, 17.92%, and 19.88%, respectively, whereas those samples in the dark were 20.74%. Trolox and ascorbic acid acted as prooxidants while their lipophilic counterparts, α-tocopherol and ascorbyl palmitate, respectively showed antioxidant properties. Similar antioxidative or prooxidative properties of the tested compounds can be observed in the results of lipid hydroperoxides and headspace volatiles. However, the prooxidant and antioxidant properties of the tested compounds were not clearly shown at 0.01 and 0.1 mM concentration. Both the type and concentration of antioxidants influenced the antioxidant capacities in riboflavin photosensitized O/W emulsions.