A spreadsheet program to optimize kinetic parameters of organic matter from laboratory pyrolysis data

Transformation of sedimentary organic matter (OM) to hydrocarbons is best modeled by assuming the total reaction suite consists of parallel degradations of ‘i’ hypothetical components following the Arrhenius equation and first order kinetics. A kerogen can be defined by characterizing each constituent component by its activation energy (Ei) their initial potentials (Xios) and a single frequency factor (A). We present a user friendly Lotus 1-2-3 program to determine A, Ei and Xio distribution of OMs using a multiple linear regression utility and programmed macros. Rock Eval (RE) S₂ curves of three heating rates are required. Equally spaced time/temperature and peak height data for S₂ curves of ‘n’ temperature steps in increasing order of heating rates are the inputs for the program. The fraction of hydrocarbon generated (f) from 19 hypothetical components of Ei 30, 32,34…78 Kcal/mole for ‘n’ temperature/time steps, by using frequency factor (A) value and assuming Xios=1, are calculated and set up in a ‘n×19’ matrix (matrix M). The fraction of total hydrocarbon generated (f) at ‘n’ temperature steps, obtained from the observed peak heights, are set up in a ‘n×1’ matrix (matrix L). Matrix M is suitably reduced by the program to ‘n×k’ matrix (matrix N) where ‘k’ is a variable, facilitating matrix inversion. Regressing matrix N against matrix L by the program, gives the Xios for ‘k’ Ei components along with a standard error (ERR) of Y estimates and R². Xios and A are then optimized iteratively by varying A values and selecting the solution associated with the lowest ERR value. Results of applying the program on data sets of two widely different types of samples from Indian basins are shown. They match the results obtained from the more sophisticated proprietary software.     

利用Notes建立中小企业的OA系统

阐述了如何通过较低的投入来实现中小企业的办公自动化管理。     

地市级气象局Lotus Notes邮件系统的管理和维护

本文介绍了地市级气象部门 Lotus/Notes 邮件系统的日常管理和维护,对系统的用户管理,数据库管理、系统的备份和恢复做了具体的阐述。     

基于Lotus Domino平台的学校OA系统的设计与实现

目前大多数学校都是通过人工传达的方式进行公文的审批,这样的办公模式极大地降低了工作效率,限制了各部门之间信息的交流与共享。如何使学校教职工从繁重的传统办公模式中解脱出来,提高办公效率,是各学校急需解决的问题．本文介绍了基于Lotus Domino平台的学校OA系统的设计与实现。     

办公自动化在电信大客户管理中的应用

根据电信企业的现状及业务特点,论述了大客户管理系统的设计思想以及系统的主要功能。     

基于Lotus Notes的工作流技术在OA系统中的应用

基于工作流的开发方法是随着计算机技术的发展以及计算机网络的广泛应用而提出来的，它为许多具有群组协同特征的应用开发提供了理论指导。结合实际介绍了工作流技术开发基于Lotus Notes平台的办公自动化系统(OA)方面的应用，并探讨了有关的技术问题。     

基于Notes的报社稿费管理系统的设计和实现

本文提出了建立计算机稿费管理系统的思路，设计并实现了基于Lotus Notes/Domino的稿费管理系统，并对其中的关键技术进行了深入探讨。     

Web OA中的用户注册机制及其实现技术

探讨了Lotus Domino／Notes的用户注册机制的核心技术，分析、比较了Domino自带的几种注册技术的优缺点。为了更好地实现系统的集成性，提供更大的灵活性和安全性，提出把注册模块从Domino系统中分离的思想，并给出了一个具体的基于Web的用户注册的实现技术及相关代码。     

机械表面超疏水防冰技术应用研究进展北大核心

在工业领域,机械设备表面覆冰会极大地影响设备的使用,甚至会造成严重的事故。研究表明:在机械表面上构筑超疏水表面能够有效抑制和延缓结冰的发生。这种新型的被动防冰方法,具有耗能低、防冰效果优良等优点,展现出了良好应用前景。阐述超疏水表面的疏水原理,总结常用制备超疏水表面的材料和方法,重点综述了超疏水表面防冰的3种作用机制,以及现阶段提高超疏水表面机械稳态性的研究进展。     

Condensed tannins from Lotus corniculatus and Lotus pedunculatus exert different effects on the in vitro rumen degradation of ribulose‐1,5‐bisphosphate carboxylase/oxygenase (Rubisco) protein

Condensed tannins (CT) or proanthocyanidins (PA), which occur in a restricted range of forages, have the ability to interact with proteins and enzymes and can influence the digestion of plant protein in the rumen. We compared the effects of CT extracts from Lotus corniculatus and pedunculatus on degradation of the principal leaf protein, ribulose‐1,5‐bisphosphate carboxylase/oxygenase (Rubisco), by rumen microorganisms. Total soluble leaf protein extracted from white clover (Trifolium repens ) was incubated with fresh rumen fluid from sheep and a range of concentrations of each CT extract. The rate of degradation of the large (LSU) and small subunit (SSU) of Rubisco was quantified by fractionating the proteins in samples taken from in vitro rumen incubations using sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS‐PAGE) and imaging densitometry. To deduce the effects of the CT extracts, experiments were performed in the presence (CT inactive) and absence (CT active) of polyethylene glycol (PEG; MW 3350). The two CT extracts differed markedly in their effects on the degradation of the LSU and SSU of Rubisco. At concentrations of 0.89 and 1.79 mg CT mg ⁻¹ total soluble leaf protein, the CT extract from L pedunculatus was more effective at preventing the degradation of the LSU and SSU by rumen microorganisms than the CT extract from L corniculatus. At a concentration of 1.79 mg CT mg ⁻¹ total soluble leaf protein, the CT extracts from L corniculatus and pedunculatus prevented about 0.75 and 0.83 of the LSU and about 0.69 and 0.86 of the SSU, respectively, from being degraded. Addition of PEG removed the inhibition and almost complete degradation of these proteins occurred, as was the case in incubations without CT extracts. The results of this study suggest that the concentration of CT in the diet and the chemical structure which affects the activity of the CT needs to be considered when assessing the effects of CT on protein metabolism in ruminants. © 1999 Society of Chemical Industry