An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Abstract This paper presents an evaluation of infill drilling opportunities in a mature waterflood. Different infill drilling configurations for increased oil recovery are compared using a ranking scheme. The field has been on production since 1976. The field has a complex development history, with periods of primary recovery, shut-in, 5-spot, inverted 9-spot, and direct line-drive waterflood. The field is currently undergoing a linedrive waterflood. The challenge is to find new infill drilling opportunities and determine optimal well spacing to maximize oil production. Traditional infill drilling evaluations either use empirical techniques based on ad-hoc esimates of drainage areas or reservoir simulation of the field-level benefits of an infill drilling program. The former approach ignores the impact of reservoir heterogeneities while the latter approach makes it difficult to evaluate the contribution that each infill well makes to the field-level benefit. Our approach isolates the impact of each infill well and provides a fast and novel methodology to evaluate the incremental benefit while accounting for reservoir heterogeneity, well conditions, pattern configuration, injection rates, and voidage replacement ratio. This type of analysis helps optimize the number of wells to be drilled and at the same time leads to increased oil recovery through better waterflood management. Streamline analysis was used to identify dead spots and regions of unswept oil in a part of the field. A novel waterflood management workflow was used to evaluate new infill well configuration strategies to increase oil recovery and better manage the waterflood. Optimization studies were also conducted to minimize the number of wells with the right combination of injectors and producers and obtain significant incremental benefits. Work is underway in the field to implement these recommendations and early results point to the success of this approach. This paper presents a novel approach for evaluating the impact of infill drilling. The marginal utility of each infill well is calculated and then is used to optimize the number of wells and maximize oil recovery. The approach presented can be used to quantify the impact of infill drilling and increase oil rate and recovery in similar reservoirs.
Abstract: With the increasing demand of lithium (Li) used for energy storage, there is a need for diversified Li sources beyond brines. Among the minerals that can satisfy this need, spodumene is most often used for its high Li content and natural abundance. However, the traditional approach to process spodumene is costly and energy-intensive, requiring that the mineral be transformed from its naturally occurring α phase into the more reactive β phase at temperatures exceeding 1000 °C [1, 2]. Acid leaching is then used to extract Li, followed by neutralization to precipitate Li in the form of Li 2 CO 3 , a common precursor for the synthesis of Li-ion battery cathodes. Recently, we have developed an improved procedure to extract Li directly from α-spodumene, which can be performed at lower temperatures and avoids the use of acids. Li 2 CO 3 can be formed with > 90% yield at 750 °C by reacting α-spodumene with inexpensive additives. Following its extraction from spodumene, Li 2 CO 3 can be isolated with high purity by washing the sample using deionized water [3]. The Li extraction process introduced above presents a low-energy and acid-free route to obtain Li 2 CO 3 directly from spodumene, thereby fostering a more sustainable and efficient utilization of natural minerals to produce precursors that are essential for battery industry. We will also demonstrate how the in-situ formation of Li 2 CO 3 opens new opportunities for the direct synthesis of battery materials from raw ores (α-spodumene). References: [1] Karrech, A., et al., A review on methods for liberating lithium from pegmatities, Minerals Engineering , 2020. 145 . [2] Yelatontsev, D. and Mukhachev A., Processing of lithium ores: Industrial technologies and case studies – A review, Hydrometallurgy , 2021. 201 . [3] Shilong, W., Nathan, S., et al., Direct lithium extraction from α-spodumene through solid-state reactions for sustainable Li 2 CO 3 production, under review .
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Potentials for the thermal cell (25°C) as a function of the concentration of and temperature are reported. The thermal cell potentials are combined with isothermal potentials for the silver‐silver chloride electrode at elevated temperatures to calibrate external electrodes as pseudothermodynamic standards for the investigation of electrochemical processes in high temperature aqueous systems.
First principles computation can be used to investigate an design materials in ways that can not be achieved with experimental means. We show how computations can be used to rapidly capture the essential physics that determines the useful properties in different applications. Some applications for predicting crystal structure, thermodynamic and kinetic properties, and phase stability are discussed. This first principles tool set will be demonstrated with applications from rechargeable batteries and hydrogen storage materials.
Reactions proceeding through cationic intermediates that lack a Lewis or Brønsted basic site present a challenge for traditional asymmetric catalysis based on chiral metals or organocatalysts. We present an enantioselective ring opening of tetrasubstituted meso-aziridinium ions with alcohol nucleophiles proceeding through a chiral ion pair with a binaphthol-phosphate anion. The reaction is initiated by silver-induced ring closure of beta-chloroamines using the Ag salt of the chiral anion as in situ generated catalyst. Use of insoluble Ag2CO3 as silver source is essential to obtain high enantioselectivity; we believe the chiral phosphate acts as a "chiral anion phase transfer catalyst" to bring silver ion into the organic phase. The chiral anion concept can also be extended to the related asymmetric opening of meso-episulfonium ions generated by protonation of trichloroacetimidates vicinal to sulfides.
More than one in ten American grandparents raise a grandchild for at least six months, with most of these providing care for three years or more. This longitudinal study, utilizing data from the National Survey of Families and Households, identifies the pre-existing personal characteristics and contextual variables which are predictive of individuals becoming primary caregivers for their grandchildren. Contrary to hypothesis, pre-caregiving attitudes concerning intergenerational solidarity bore little relationship to the likelihood of becoming a caregiver. In contrast, being female, younger, African American, and having not completed high school were significantly predictive of becoming a custodial grandparent. Implications of these findings for research, practice, and policy in gerontology, mental health, and related areas are discussed.
The hydridoruthenate [(solv)Na][Cp*(iPr2MeP)RuH2] (1; solv = THF or Et2O) provided access to the Ru metallostannylene Cp*(iPr2MeP)(H)2RuSnDMP (DMP = 2,6-dimesitylphenyl) (2) and metalloplumbylene Cp*(iPr2MeP)(H)2RuPbArTrip2 (ArTrip2 = 2,6-bis(2,4,6-triisopropylphenyl)phenyl) (3) compounds by salt metathesis reactions with the corresponding [ArEX]2 precursors. The Sn complex 2 reacted nucleophilically with MeI to cleanly generate the addition product Cp*(iPr2MeP)(H)2RuSnI(Me)DMP (4), while a complex mixture was observed for Pb complex 3. A Ru monohydride synthon generated from 1 also provided access to the chlorostannylene and bromoplumbylene complexes Cp*(iPr2MeP)(H)Ru[SnCl(DMP)] (5) and Cp*(iPr2MeP)(H)Ru[PbBr(ArTrip2)] (6), respectively.
