Ergosterol as an objective indicator for grape rot and fungal biomass in grapes

Sound grapes are an essential prerequisite for the production of high-quality wines. However, pricing of grapes is so far mainly based on the must weight of grape deliveries, although e.g. highly botrytised grapes become raisined bringing about higher contents of soluble solids than sound ones. Besides the desired ‘noble rot’, in particular infection of unripe fruits by grape rot decreases the perceptual quality by destroying fruit flavours typical of the grape variety, furthermore leading to off-flavours, off-odour, bitterness and colour-loss. Moreover, the formation of mycotoxins, in particular ochratoxin A, associated with fungal infestation highly affects food safety of the products. Consequently, there is a strong need of an objective assessment of the phytosanitary status of grapes to be used for vinification and other grape derived products. To date, the commonly applied visual examination is subjective, and particularly challenging when grapes were mechanically harvested. Objective methods suggested in the literature, such as the analysis of major and secondary metabolites of moulds and the determination of related enzyme activities, are requiring tedious sample preparation being generally time-consuming. Furthermore, these methods are prone to interferences, and mostly lacking selectivity and sensitivity.Ergosterol is a characteristic component of the fungal cell membrane, while it is completely or nearly absent in animal, plant and bacterial cells. Thus, our group proposes ergosterol as a specific and quantitative marker for fungal infection of grapes. Mould strains relevant for grape rot were demonstrated to contain considerable amounts of ergosterol. In grapes infected with several pure mould strains and in naturally contaminated grapes, ergosterol was unambiguously detected and quantitated. In contrast, only traces were found in sound grapes, presumably originating from the presence of ubiquitous yeasts and moulds. Ergosterol levels highly correlated with the degree of fungal decay in blended samples of mashes made from sound and rotten berries. An analytical HPLC-method for the quantitation of ergosterol was developed allowing a simple and objective evaluation of the phytosanitary status of grapes, thus enabling fair and incentive payments between grape growers and wineries.     

Quantitative estimation of Campylobacter cross-contamination in carcasses and chicken products at an abattoir

This study aimed to investigate Campylobacter contamination in carcasses and chicken products derived from a Campylobacter-negative flock when the flock is slaughtered immediately after a Campylobacter-positive flock. The first 2 flocks slaughtered on 10 different dates were investigated at an abattoir. Eighteen of the 20 flocks tested were positive for Campylobacter. A Campylobacter-negative flock was slaughtered immediately after a Campylobacter-positive flock on only 1 of the 10 slaughter dates. In this case, Campylobacter was detected in the carcasses and chicken products originating from the Campylobacter-negative flock, and all the flaA genotypes of these isolates were identical to those present in the caecal contents, carcasses, and chicken products from the Campylobacter-positive flock. The Campylobacter concentrations in the products originating from the Campylobacter-negative flock were: close to the enumeration limit (1.7 log₁₀ cfu/carcass) in the carcass samples; and below the enumeration limit (2.0 log₁₀ cfu/g) in the liver samples. The mean Campylobacter concentrations in the carcasses and liver products originating from the 18 Campylobacter-positive flocks were 3.8 log₁₀ cfu/carcass and 2.6 log₁₀ cfu/g, respectively. While 91% (246/270) of chicken products originating from Campylobacter-positive flocks were positive for Campylobacter, chicken products originating from the remaining Campylobacter-negative flock were free from Campylobacter cross-contamination by slaughter prior to a Campylobacter-positive flock. These results prove that slaughtering Campylobacter-negative flocks does not introduce Campylobacter into the abattoirs and indicate that although carcasses and chicken products originating from the Campylobacter-negative flock were cross-contaminated with Campylobacter from the Campylobacter-positive flock slaughtered immediately before, the Campylobacter contamination levels were lower than those in carcasses and chicken products from Campylobacter-positive flocks. Based on these findings, the reduction of Campylobacter prevalence in broiler flocks should be taken as an effective control measure for preventing introduction of Campylobacter into abattoirs and consequently for reducing Campylobacter prevalence in chicken products in addition to the good hygienic practice at abattoirs and logistic slaughter.     

中国南方海相页岩气中氮气成因及其指示意义

中国南方海相页岩气资源丰富,部分页岩气气体组分中氮气（N₂）含量所占比例较大。依据川西南地区、长江三峡地区和贵州省岑巩地区页岩气地质、地球化学特征,结合黄金管热模拟实验,系统研究了页岩气中N₂的成因及其指示意义。结果表明,页岩气中N₂为典型壳源有机成因,高氮页岩气主要来源于干酪根的晚期热解,高氮含量是早期生成的原油裂解气未运聚成藏或成藏后受到破坏的体现。因此,页岩气资源量有限,主要证据有以下3个方面。首先,页岩中的干酪根类型是典型腐泥型,保存条件良好的情况下页岩气应以原油裂解气为主,但页岩气类型的识别表明高N₂含量的页岩气属干酪根热解气或原油裂解气和干酪根热解气的混合气。其次,通过对寒武系来源的原油样品进行黄金管热模拟实验,发现高氮页岩气碳同位素值比热模拟实验测得的原油二次裂解气碳同位素值明显偏重。最后,随着有机质演化程度的升高,N₂含量升高,而且保存条件较好的页岩气井,氮气含量较低,含气性较好,氮气含量对保存条件具有指示意义。     

油藏开发流体动力地质作用——以胜坨油田二区为例

研究了注水开发36年、含水已高达95%处于特高含水阶段的胜坨油田二区,提出油藏开发流体动力地质作用是控制研究区储层宏观、微观和渗流三大类参数变化规律和变化机理及剩余油形成分布的主因,建立了油藏开发流体动力地质作用的概念,论述了产生的地质环境、动力来源及动力作用方法.论证了油藏开发流体动力地质作用能长期持久进行的原因.     

Biogenic amines content in traditional dry fermented sausage Petrovská klobása as possible indicator of good manufacturing practice

The aim of this study was to determine the content of nine biogenic amines (tryptamine, phenylethylamine, putrescine, cadaverine, histamine, serotonin, tyramin, spermidine and spermine) and total biogenic amines in traditional dry fermented sausage Petrovská klobása at the end of drying period, as possible indicators of good manufacturing practice (GMP).Chromatographic separation of dansyl chloride derivatizated amines was completed in 8 min. Analyses were performed by HPLC-DAD on Eclipse XDB-C18 column. Tryptamine and spermine were determined in all analyzed samples, while histamine, serotonin and spermidine were not detected in any samples. Average content of individual biogenic amine ranged from 5.54 mg/kg (putrescin) to 75.1 mg/kg (tryptamine) and total content of biogenic amines varied from 77.8 mg/kg to 174 mg/kg.The results obtained in this study provided no evidence for deviations from good manufacturing practice in Petrovská klobása production.     

松辽盆地南部十屋断陷地表烃类异常特征及油气指示意义

地表油气化探技术根据油气微渗漏在地表的异常显示特征预测深部油气藏,已经有70余年历史。大多数人都认可油气藏能发生油气微渗漏这一自然现象,但对深部油气藏与地表化探异常之间的复杂关系尚存疑虑。十屋断陷已知油气藏油气微渗漏检测结果显示,该区各项化探指标均为低背景非均匀地球化学场特征,异常点浓度较高;与油气藏有关的异常呈环状或复杂环状形态,受断层和盖层条件影响而产生的异常为条带状或块状形态。油藏和油气藏微渗漏异常特征不同,气田上方异常强度低,为简单环状;而油气田上为复杂环状(环内也有部分指标异常)。     

Colour measurement as indicator for controlling the manufacture and storage of enteral formulas

Reflectance colour measurement was used to control the browning reaction during the manufacture (untreated, UHT, standardisation and bottle sterilisation) and storage (4, 20, 32 and 55 °C from 1 to 36 weeks) of two types of enteral formula (3.7% and 5.4% protein). Precision studies showed coefficients of variation of 0.19%, 4.77% and 1.02% for L¹, a¹ and b¹ parameters respectively. The a¹ and b¹ parameters proved useful to monitor the manufacture of these products. No statistically significant changes were observed during storage at 4 °C. At 55 °C the parameters a¹ and b¹ increased for both types of formula. However, at 20 and 32 °C, the a¹ parameter was useful for the formula with 3.7% protein and the b¹ parameter for that with 5.4%. Colour measured as reflectance was strongly correlated with colour absorbance at 420 nm, especially during storage at 20 °C. Likewise, a strong correlation was observed between nutritional value (measured as lysine loss) and colour. Colour measurement is a simple and fast method to control different processing and storage conditions of enteral formulas, and may also be useful as an indirect measurement of nutritional value.     

构造体制转换与成藏作用——以鄂尔多斯盆地为例

构造体制转换在控制油气成藏中起着决定作用。其对成藏的控制作用可分为直接和间接2种方式。前者指构造体制转换使盆地构造应力场强度和性质发生变化，于盖层岩系中发育各种形式褶皱和断裂构造，组成了流体输运一定位网络，使物质和能量在盆地内重新分布；而后者指构造体制转换引起盆地沉积场、温度场及化学场等变化，并最终控制油气生、运、储。通过对鄂尔多斯盆地典型实例的剖析，认为多板块相互作用是盆地大规模成藏作用发生的根本动力，它控制着盆地的构造演化和沉积充填样式；同时，致使盆地不同部位形成差异升降和反转构造2种不同的构造样式。盆地中部构造作用微弱地带形成差异升降，而盆地边缘构造作用强烈部位发育反转构造。受其控制，盆地中部以构造-岩性圈闭为主，而盆地边缘则发育构造圈闭。抬升作用形成的区域不整合以及构造反转作用形成的断裂和裂隙系统，构成了油气运移的主要通道；油气发生垂向和侧向运移，最终在反转构造上升盘或隆起与坳陷转换部位聚集。     

四川盆地东南部页岩气同位素分馏特征及对产能的指示意义

页岩气甲烷碳同位素是研究页岩气同位素分馏特征及产出过程的重要指标。选取四川盆地东南部及盆缘转换带内6大区块10口页岩气井上奥陶统五峰组-下志留统龙马溪组页岩,通过现场含气量测试过程中页岩气甲烷碳同位素变化,研究不同压力系统、不同小层下甲烷碳同位素分馏特征,探讨页岩气同位素与物性、含气性关系,并结合实际排采数据,对典型页岩气井产出阶段进行划分。页岩气解吸过程中,逐渐升高,甲烷碳同位素逐渐变重;超压页岩气甲烷碳同位素整体较小,从盆缘外部向内部,甲烷碳同位素逐渐变轻。纵向上,随着深度的增加,甲烷同位素整体变轻;页岩孔隙度越大、游离气含量越高、页岩保存条件越好,甲烷碳同位素分馏作用就越不明显。最后,选取武隆向斜L井岩心现场解吸气样,通过甲烷同位素分馏,对页岩气解吸阶段进行划分,并将排采气同位素与现场解吸气同位素进行比对。该井排采气的δ¹³C₁值对应现场岩心连续解吸0.9 h释放气体的δ¹³C₁值,其采收率约为24.8%,尚处于初期排采阶段。     

异常压力与油气藏的同生关系——以库车坳陷为例

以库车坳陷克拉2气田为例，研究挤压背景异常压力与油气成藏的关系。大规模抬升早期阶段是天然气注入的主要时期，同时也是气藏压力急剧增加的时期。克拉2气藏的成藏模式总体为深大断裂沟通储集层和烃源岩层，在深部超压的驱动下油气运移至储集层成藏。储集层在成藏早期不是强超压，并且不完全封闭，可以存在流体排出过程。随着天然气替换构造圈闭中的地层水和成岩作用逐渐进行，储集层封闭性加强，气藏压力不断升高，最后形成超压气藏，气藏强超压形成于距今2Ma以来。异常高压与气藏的形成均是构造作用和保存条件演化的结果，二者本身不具备因果关系。气源断层与盖层完整的匹配是控制天然气成藏的关键因素。图4参16     

环烷酸在油品与萃取剂两相间表观分配比的研究

通过对乙醇溶液与直馏柴油体系、复合溶剂与直馏柴油体系、复合溶剂与减一线油体系的研究表明 ,尽管油品中的环烷酸为复杂混合物 ,但仍可以近似将其按单一溶质处理 ,用油品酸值代替环烷酸摩尔含量来计算环烷酸在油品与萃取剂间的表观分配比。实验结果表明 ,不同剂油比时的表观分配比为一稳定数值 ,可用于指导生产实践。环烷酸在 95 %乙醇与直馏柴油间、复合溶剂与直馏柴油间、复合溶剂与减一线油间的表观分配比分别为 :2 .0± 0 .2 ,39± 3,15± 1.5。     

Downhole Heating: Productivity Ratio Improvements—Dangers of Misconceptions

Stimulating the well productivity of reservoirs that contain viscous oil is initially often carried out by heating the near-wellbore region. Heating lowers the oil viscosity so that the oil can flow faster under the same pressure differential, but for maximum rewards how much of the reservoir must be heated and to what temperature should it be heated? This paper presents a boundary condition approach to give guidance to these questions. We examine the effectiveness of downhole heating on the productivity using a simple radial model with viscosity changes. We find that for the same temperature rise the productivity improvement is greater for high viscosity oils than for low viscosity ones. We also find that there is a maximum beneficial temperature rise for a given radius of heating, and that for the same energy input it is probably more beneficial to heat deeper into the reservoir at a lower temperature than high heating for a smaller radius. If only 17% of the reservoir radius is heated, then the maximum productivity increase is typically no more than a factor of around 4 no matter how large is the temperature increase in the heated zone. The exact improvement depends on the initial oil viscosity, the initial oil temperature, and its temperature dependence.     

工业色谱仪和DCS之间的串行通讯

介绍了一种在工业上被广泛应用于在线色谱仪和DCS之间的串行通讯总线及以Modbus协议为基础的RS-485串行通讯的实现方法。通过RS-485建立的多点式数据网络，实现了工业色谱仪数据通信的数字化，解决了过去4～20mA模拟信号传输数据带来的误差和繁重的工作量，提高了工业色谱仪数据传输的准确性，降低了硬件的投资成本，并且为工业色谱仪实现远程操作和控制奠定了基础。     

吐哈油田稠油开采掺稀泵泵压与掺稀比关系研究

针对新疆吐鲁番地区玉东油田稠油具有粘度高、密度大、埋藏地深的特点,在开采时,选用泵上掺稀降粘举升开采工艺。对掺稀泵泵压与掺稀比的关系进行了研究,分析了掺稀泵泵压形成的原因,推导出了掺稀泵泵压与掺稀比的关系。现场应用时可以从掺稀泵的压力表上直观地看到掺稀泵的泵压,从而可以大致估算出所掺入的稀油量是否足够。     

Synergism between MC-MA-MCNR<Superscript>2</Superscript> terpolymer and EVA as a cold flow improver in diesel fuel

A novel terpolymer, MC-MA-MCNR², derived from tetradecyl methacrylate (MC), maleic anhydride (MA), and methacrylamide (MCNR²) was synthesized. The ability of MC-MA-MCNR² was evaluated as a cold flow improver in diesel fuel, and the interactions of MC-MA-MCNR² with several kinds of copolymer were studied. To provide a better understanding of the synergistic mechanism, microscopy was used to study the crystal conformation when MC-MA-MCNR² and EVA (ethylene-vinyl acetate) are mixed into a diesel fuel. The results indicate that using blends of MC-MA-MCNR² and EVA, one can obtain a satisfactory cold filter plugging point depression. Based on the microscopy experiment, the synergism mechanism was discussed. Published in Khimiya i Tekhnologiya Topliv i Masel, No. 4, pp. 21–23, 2007.     

Treatment of oilfield production wastewater by an integrated process

Laboratorial scale experiments were performed to investigate the performance of an integrated process including demulsification, coagulation, and reactive oxygen species (ROS) oxidation for treating oilfield waste drilling fluid. The optimum dosages for demulsifier, polyaluminium chloride and polyacrylamide are 2, 0.6 and 3 mg/L, respectively. The optimum ROS oxidation conditions are ROS molecules content = 350 mg/L, energy consumption = 30 Wh, reaction time = 40 min, and initial pH = 6.5. Results show that 96.3% of oil can be recovered from the waste, and the quality of the final effluent can satisfy the national discharge standard after ROS oxidation.     

裂解碳十作稀释剂的双环戊二烯解聚过程

在反应精馏塔中,以乙烯装置副产裂解碳十(C10)作为稀释剂,考察了双环戊二烯(DCPD)的液相解聚过程,并对稀释比(裂解C10与粗DCPD的质量比)、解聚温度、反应时间、回流比等工艺条件进行了优化。结果表明,裂解C10可有效减少塔釜多聚物的产生,同时增加DCPD的解聚深度,使产品CPD收率高于92%;在稀释比为0.25～0.50,解聚温度为180℃,反应时间为3 h,回流比为2.5的优化条件下,产品CPD纯度达98%(质量分数)。