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A hybrid machine learning optimization algorithm for multivariable pore pressure prediction

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Petroleum Science 2024年第1期21卷 535-550页

作者： Song deng Hao-Yu Pan Hai-Ge Wang Shou-Kun Xu Xiao-Peng Yan Chao-Wei Li Ming-Guo Peng Hao-Ping Peng Lin Shi Meng Cui Fei Zhao School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhou213164JiangsuChina Tubular Goods Research Institute of CNPC Beijing102249China CNPC Engineering Technology R&d Company Limited Beijing102206China

Pore pressure is essential data in drilling design,and its accurate prediction is necessary to ensure drilling safety and improve drilling *** methods for predicting pore pressure are limited when forming particular structures and *** this paper,a machine learning algorithm and effective stress theorem are used to establish the transformation model between rock physical parameters and pore *** study collects data from three *** 1 had 881 data sets for model training,and Wells 2 and 3 had 538 and 464 data sets for model *** this paper,support vector machine(SVM),random forest(RF),extreme gradient boosting(XGB),and multilayer perceptron(MLP)are selected as the machine learning algorithms for pore pressure *** addition,this paper uses the grey wolf optimization(GWO)algorithm,particle swarm optimization(PSO)algorithm,sparrow search algorithm(SSA),and bat algorithm(BA)to establish a hybrid machine learning optimization algorithm,and proposes an improved grey wolf optimization(IGWO)*** IGWO-MLP model obtained the minimum root mean square error(RMSE)by using the 5-fold cross-validation method for the training *** the pore pressure data in Well 2 and Well 3,the coefficients of determination(R^(2))of SVM,RF,XGB,and MLP are 0.9930 and 0.9446,0.9943 and 0.9472,0.9945 and 0.9488,0.9949 and *** achieves optimal performance on both training and test data,and the MLP model shows a high degree of *** indicates that the IGWO-MLP is an excellent predictor of pore pressure and can be used to predict pore pressure.

关键词： Pore pressure Grey wolf optimization Multilayer perceptron Effective stress Machine learning

One-pot and One-step Cu(0)-mediated Reversible-deactivation Radical Polymerization of N-Isopropylacrylamide(NIPAM) in Water

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Chinese Journal of Polymer Science 2024年第1期42卷 1-6,I0004页

作者： Zi-Shan Li Jing Lyu Bei Qiu Ying-Hao Li Ruth Foley Ri-Jian Song Melissa Johnson Qiang Geng Wen-Xin Wang Institute of Precision Medicine(AUST-IPM) Anhui University of Science and TechnologyHuainan 232001China Charles Institute of dermatology School of MedicineUniversity College DublinDublin D04 V1W8Ireland

Copper(0)-mediated reversible-deactivation radical polymerization(Cu(0)-mediated RdRP) of the water-soluble monomer Nisopropylacrylamide(NIPAM) has been challenging with the problems of high dispersity, poor control over the molecular weights(MWs) or complex or multi reaction steps, etc. In this work, we report the well-controlled polymerization of NIPAM in water via a facile one-pot and one-step Cu(0)-mediated RdRP. The results of this approach show that the key for kicking off the Cu(0)-mediated NIPAM RdRPs is to ensure sufficient Cu~I at the very beginning, and the key to achieve a well-controlled chain growth is to provide adequate deactivation strength during the polymerization process. For NIPAM, which has a high propagation rate constant, the deactivation control can be effectively enhanced by extra adding deactivator(i.e., Cu~II) to the system. Moreover, a low reaction temperature(4 ℃) is necessary in the controlled synthesis of higher MW poly(Nisopropylacrylamide)(PNIPAM) to avoid the compromise in control caused by the phase transition from its lower critical solution temperature(LCST). Through this new kinetically controlled strategy, PNIPAMs with well-defined structure, narrow molecular weight distributions(MWds) and varied MWs were successfully achieved.

关键词： Cu(0)-mediated RdRP N-isopropylacrylamide Propagation deactivation Reaction parameters

Effect of CO_(2)flooding in an oil reservoir with strong bottom-water drive in the Tahe Oilfield,Tarim Basin,Northwest China

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Energy Geoscience 2024年第1期5卷 230-233页

作者： Li Zhang Haiying Liao Maolei Cui R&d Center of Sustainable development of Continental Sandstone Mature Oilfield Beijing100083China Petroleum Exploration and Production Research Institute SinopecBeijing100083China

The dissolution and diffusion of CO_(2)in oil and water and its displacement mechanism were investigated by laboratory experiment and numerical simulation for Block 9 in the Tahe oilfield,a sandstone oil reservoir with strong bottom-water drive in Tarim Basin,Northwest *** parameters were analyzed as solubility ratio of CO_(2)in oil,gas and water,interfacial tension,in-situ oil viscosity distribution,remaining oil saturation distribution,and oil *** results show that CO_(2)flooding could control water coning and increase oil *** the early stage of the injection process,CO_(2)expanded vertically due to gravity differentiation,and extended laterally under the action of strong bottom water in the intermediate and late *** CO_(2)got enriched and extended at the oil-water interface,forming a high interfacial tension zone,which inhibited the coning of bottom water to some extent.A miscible region with low interfacial tension formed at the gas injection front,which reduced the in-situ oil viscosity by about 50%.The numerical simulation results show that enhanced oil recovery(EOR)is estimated at 5.72%and the oil exchange ratio of CO_(2)is 0.17 t/t.

关键词： Strong bottom-water drive reservoir CO_(2)flooding Enhanced oil recovery Coning of bottom water Tahe oilfield Tarim Basin Northwest China

Photovoltaic waste management in sub-Saharan Africa:current practices in Burkina Faso

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Waste disposal and Sustainable Energy 2024年第2期6卷 271-282页

作者： Kodami Badza Yrebegnan Moussa Soro Marie Sawadogo Laboratoire Energies Renouvelables et EfficacitéEnergétique Institut International d'Ingenierie de I'Eau et de I'Environnement(2iE)01 BP 594 OuagadougouBurkina Faso

Sub-Saharan Africa is witnessing a proliferation of photovoltaic(PV)waste due to the increasing number of solar PV power *** waste(panels,batteries,electrical cables,mounting structures,and inverters)consists of elements such as mercury,cadmium,chromium,lead,copper,aluminum,fluorinated compounds,and plastics that are toxic to human health and the environment if a proper management system is not *** many studies worldwide have focused on PV waste management,very few have been conducted in sub-Saharan *** study aims to investigate the current PV waste management system in Burkina Faso,determine stakeholder profiles,and propose strategies to enhance the existing *** research,interviews,questionnaires,and field visits were used in the *** survey showed that young people,mainly under 30 years of age and with a primary education,dominate(70%)in terms of PV waste collection and repair activities,while the more technical recycling and export activities are carried out mainly(88%)by stakeholders older than 40 years and with a secondary education(60%).Among the older stakeholders,100%are aware of the hazardous nature of PV waste,whereas 36%are young *** an environmental perspective,the main source of contamination observed is the release of lead-rich sulfuric acids into water and soil during the collection and repair *** the recycling of batteries and electrical cables,toxic fumes are emitted into the air,and recycling residues rich in toxic substances are *** reduce risks to human health and the environment when managing PV waste,the introduction of legislation,the multiplication of collection points and appropriate infrastructures,the training and awareness-raising of stakeholders,and the extended responsibility of manufacturers are *** on the economic feasibility of setting up formal management structures are needed to complete this work.

关键词： Photovoltaic waste Sub-Saharan Africa Waste management Recycling Batteries Incineration

LE dEMI-SICLE, dE MOÏSE AU FISCUS IUdAICUS. HISTOIRE d’UNE TÉLÉOLOGIE

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Journal of Ancient Civilizations 2024年第1期39卷 73-98,124页

作者： Michaël Girardin Universitédu Littoral-Côte d’Opale

Many sources are brought together in scholarship in order to write the linear story of a specific tax,the half shekel tax paid each year by the Jews to the Temple of Jerusalem and,then,confiscated by the fiscus Iudaicus in Roman *** do these sources refer to the same tax?In this paper,I defend the idea that the linearity of this story is a *** taxes were levied and justified by the memory of a Biblical tax,but they are all different in meaning,in administration and sometimes even in *** story is a political one:how to justify a tax in ancient Judaism?

关键词： didrachm fiscus Iudaicus half shekel Jerusalem Temple Roman Judea taxation teleology

Mn-doped SrCoO_(3-δ) Perovskite Oxides for Ethylene Production via Chemical Looping Oxidative dehydrogenation of Ethane

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China Petroleum Processing & Petrochemical Technology 2024年第3期26卷 53-62页

作者： Li Zhi Liu Linjiao Hao daijun Ren Xiaohang Shen Fangxia Li Xin Yu Anping Luoyang R&d Center of Technology of Sinopec Engineering(Group)Co.Ltd. Luoyang 471003China

Chemical looping oxidative dehydrogenation (CL-OdH) is an economically promising method for convertingethane into higher value-added ethylene utilizing lattice oxygen in redox catalysts, also known as oxygen carriers. Inthis study, perovskite-type oxide SrCoO_(3-δ) and B-site Mn ion-doped oxygen carriers (SrCo_(1-x)MnxO_(3-δ), x=0.1, 0.2, 0.3)were prepared and tested for the CL-OdH of ethane. The oxygen-deficient perovskite SrCoO_(3-δ) exhibited high ethyleneselectivity of up to 96.7% due to its unique oxygen vacancies and lattice oxygen migration rates. However, its low ethyleneyield limits its application in the CL-OdH of ethane. Mn doping promoted the reducibility of SrCoO_(3-δ) oxygen carriers,thereby improving ethane conversion and ethylene yield, as demonstrated by characterization and evaluation experiments.X-ray diffraction results confirmed the doping of Mn into the lattice of SrCoO_(3-δ), while X-ray photoelectron spectroscopy(XPS) indicated an increase in lattice oxygen ratio upon incorporation of Mn into the SrCoO_(3-δ) lattice. Additionally, H2temperature-programmed reduction (H2-TPR) tests revealed more peaks at lower temperature reduction zones and a declinein peak positions at higher temperatures. Among the four tested oxygen carriers, SrCo0.8Mn0.2O_(3-δ) exhibited satisfactoryperformance with an ethylene yield of 50% at 710 °C and good stability over 20 redox cycles. The synergistic effect of Mnplays a key role in increasing ethylene yields of SrCoO_(3-δ) oxygen carriers. Accordingly, SrCo0.8Mn0.2O_(3-δ) shows promisingpotential for the efficient production of ethylene from ethane via CL-OdH.

关键词： ethane ethylene perovskite chemical looping oxidative dehydrogenation

Exploration of Green Alternatives to 6PPd (P-Phenylenediamine) Used as Antiozonant and Antioxidant in the Rubber Industry

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Materials Sciences and Applications 2024年第4期15卷 87-100页

作者： Emine demir Husnu Gerengi Kerem Savcı Gasim Altundal Canan Yüksel doğaç Çağıl Anlas Tyre Company R&d Center D&#252zce T&#252rkiye department of Mechanical Engineering Faculty of Engineering D&#252zce University D&#252zce T&#252rkiye The Koc High School &#304stanbul T&#252rkiye

Antiozonants and antioxidants are additives commonly used in the rubber industry to enhance the durability and performance of rubber products. Ozone, present in the atmosphere, can cause rubber to degrade over time through a process known as ozone cracking. These rubber additives are added to rubber compounds to protect against this degradation. They work by reacting with ozone, preventing it from attacking and breaking the molecular chains in the rubber, helping to maintain the structural integrity of the rubber product. It is now well known that 6PPd contributes to the extension of the service life of rubber products. However, recent studies have shown that 6PPd can be harmful to the environment, especially when end-of-life tyres (ELTs) are contaminated with the water. With the effect of ozone, 6PPd is converted to 6PPd quinone, which is toxic enough to kill some sensitive fish species such as Coho Salmon (Oncorhynchus kisutch). This study drew attention to new chemical compounds and natural products that can be used as antiozonants and antioxidants in the rubber industry instead of 6PPd. Although the scientific studies are promising, the fact that 6PPd is still used in production shows that more scientific studies and social awareness need to be developed in this area.

关键词： 6PPd Coho Salmon Antiozonant Antioxidant

Visceral Leishmaniasis at the National Reference University Hospital Center of N’djamena (Chad): Epidemiological, Clinical, diagnostic, Therapeutic and Prognostic Aspects

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Advances in Infectious diseases 2024年第2期14卷 478-486页

作者： Joseph Mad-Toïngué Mahamat Ali Ahmat Oumaïma Mahamat djarma Alifa Adjibera Philippe Ali Mahamat Moussa Ngakoutou Rangar Choua Ouchemi Mahamat Ali Bolti djiddi Ali Sougoudi Mamissou didi Mahamat doungous Atim Service des Maladies Infectieuses CHU de Référence Nationale N’Djamena Chad Service de Gastroentérologie et Médecine Interne CHU de Référence Nationale N’Djamena Chad Service de Pneumologie et Phtisiologie CHU de Référence Nationale N’Djamena Chad Service de Chirurgie viscérale CHU de Référence Nationale N’Djamena Chad Service de Médecine CHU de la Renaissance N’Djamena Chad

Introduction: leishmaniasis is a group of parasitic diseases caused by a parasite of the genus Leishmania transmitted by the bite of an infected vector called a sandfly. There are four forms. Visceral leishmaniasis is the most severe form. The aim of our work is to study the epidemiological, clinical, diagnostic, therapeutic and prognostic aspects of the disease in the Infectious diseases department of the Centre Hospitalier Universitaire de Référence Nationale in N'djaména. Methodology: Patients were recruited on the basis of clinical signs suggestive of visceral leishmaniasis, i.e. prolonged fever, splenomegaly and altered general condition. Biological confirmation was performed with a rapid diagnostic test using recombinant K39 parasite antigen, which is known to have good specificity and sensitivity. Epidata version 3.1 software was used to process patient data. Results: From 05/04/21 to 15/12/23, 153 positive cases were managed. The mean age of patients was 18 years, with a sex ratio of 9.2. Of these patients, 103 (67.3%) had recently stayed at gold mining sites. Patients testing positive were treated with sodium stibogluconate combined with paromomycin for 17 days. The mortality rate was 13.2%. Conclusion: Leishmaniasis is a serious and little-known disease in Chad. In order to respond to the disease, it is necessary to reinforce the capacities of health structures and to carry out appropriate actions in the outbreaks.

关键词： Visceral Leishmaniasis Gold Mining Sites Chad

Fabricating functionally graded Fe-Cr-Co permanent magnetic alloys via laser powder bed fusion

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Journal of Iron and Steel Research International 2024年第3期31卷 729-737页

作者： Ya-zhou He Ya-qing Hou Peng Shen Hao Zhang dong Zhou Hang Su Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Material digital R&d Center China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China

Laser powder bed fusion(LPBF)in-situ alloying technology offers the possibility to construct gradient materials with varied structures and *** graded Fe-Cr-Co permanent magnetic alloys were fabricated by LPBF and in-situ alloying mixed powders of Fe,Cr,and Co *** effects of different Fe,Cr and Co contents on the microstructure,magnetic properties and hardness of Fe-Cr-Co alloys prepared by LPBF were *** as-built Fe-Cr-Co alloys present a single body-centered-cubic phase and have a homogeneous distribution of *** mechanical properties and magnetic properties of the compositionally graded sample show a gradient *** the increase in Cr content,the Vickers hardness of the sample increases,and the saturation magnetization of the sample *** optimal magnetic properties in an isotropic state are given as coercivity HcB=21.65 kA/m,remanence Br=0.70 T and energy product(BH)_(max)=5.35 kJ/m^(3),which are comparable to or higher than the reported magnetic properties in an isotropic state prepared by traditional powder *** in-situ alloying technology has the potential to further explore Fe-Cr-Co magnetic materials,such as those consisting of multiple or more constituent elements,and to maximize the compositional flexibility of magnetic materials.

关键词： Fe-Cr-Co alloy Laser powder bed fusion In-situ alloying Functional material Magnetic property