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Highly luminescent zero-dimensional (0D) metal halide clusters attract widespread attention owing to strong exciton confinement and populated self-trapped states but often exhibit narrow emission a...

This study demonstrates the synthesis of 3D coordination polymers containing [Co5(OH)6]4+ layers and atomically thin cobaltate nanosheets by cleavage of CoII–carboxylate bonding, which are efficient and reusable catalysts for benzylic C(sp3)–H oxidation.

Organolead halide materials have shown promising optoelectronic properties that are suitable for light-emitting diodes (e.g., strong photoluminescence, narrow emission width, and high charge carrier mobility). However, the vast majority of them have no open porosity or open metal sites for host-guest interactions and are therefore not widely applicable in intrinsic fluorescent sensing of small molecules. Herein, we report a lead chloride-based metal-organic framework (MOF) with high porosity and stability and promising photoluminescent characteristics, performing as a sensitive, selective, and long-term stable fluorescence probe for NH3. For the first time, a homemade dynamic real-time photoluminescence monitoring system was developed, which showed that our haloplumbate-based MOF has an immediate response and an extremely low limit of detection (12 ppm) toward NH3. A variety of experimental characterization and theoretical calculations evidenced that the photoluminescence quenching was ascribed to the coordination between NH3 guests and exposed Pb2+ centers in MOFs. Moreover, a portable on-site smart NH3 detector was designed based on this haloplumbate-MOF using a 3D printer, and the quantitative recovery experiment demonstrated the effective detection of NH3 in the range of 15-150 ppm. This study opens a new pathway to design organolead halide-based MOFs to perform on-site chemical sensing of small molecules and shows their high potential to monitor safety concentrations of NH3 in different industrial sites.

Bedding-plane slip effects during hydraulic fracturing have recently gained interest in unconventional plays due to their influence in hydraulic fracture growth in vertical and horizontal directions. However, most of the current workflows cannot fully model field-scale sub-horizontal orientation of bedding planes because of complications with gridding techniques, or due to simplifications related to the use of 2D models. These challenges have motivated the assessment of 3D bedding plane interactions on well performance using the embedded discrete fracture model (EDFM) technology for field case scenarios. An efficient hydraulic fracture propagation model is used to model hydraulic fracture growth in the presence of bedding layers. The model captures shear slippage at the bedding layer interfaces and corrects the calculated stress intensity factor to account for height containment. A hydraulic fracture model, constrained by geomechanical information, is built in a corner point grid. Resulting hydraulic fracture geometries and identified bedding layer fractures are transferred to EDFM by using a 3D bedding plane generator, which places sub-horizontal polygons across the well trajectory, honoring its orientation and geometry. To locate the spatial position of bedding layers, geostatistical constrains, core analysis and petrophysical interpretations – including well image logs – can be taken into account. Lastly, a reservoir simulation model is built to evaluate the effects of bedding planes on well performance. 3D effects of bedding planes in a shale gas reservoir were captured in a field case scenario using numerical models. Higher contribution to production was observed in the results of this study. The main reasons are larger fracture lengths generated along the pay zone caused by bedding plane influence in the fracture propagation process and shear slippage along bedding plane fractures, which create a larger effective conductive surface area. When modeling bedding planes, computational efficiency is substantial due to the EDFM method, preserving spatial orientation and geometry of each bedding plane. Direct assessment of bedding plane properties is provided, which highlights the importance of capturing their interactions with hydraulic fracture growth and well performance. A seamless integration of bedding plane models can be achieved in an efficient workflow that provides key lessons for future fracture design and well spacing optimization.

Ultrafine gold nanoclusters (Au-NCs) are susceptible to migrate and aggregate, even in porosity of many crystalline solids. N-heterocyclic carbenes (NHCs) are a class of structurally diverse ligands for stabilization of Au-NCs in homogeneous chemistry, showing catalytic reactivity in CO 2 activation. Herein, for the first time, we demonstrate a heterogeneous nucleation approach to stabilize ultrasmall and highly dispersed gold nanoclusters in a metal-free NHC-functionalized porous matrix. The sizes of gold nanoclusters are tunable from 1.3 nm to 1.8 nm based on the interpenetration of metal-organic framework (MOF) topology. Control experiments using amine or imidazolium-functionalized MOFs afforded aggregation of Au species. The resultant Au-NC@MOF composite exhibits steady and excellent activity in photocatalytic CO 2 reduction, superior to the control mixtures without NHC-ligand stabilization. The mechanistic studies reveal the synergistic catalytic effect of MOFs and Au-NCs through the MOF-NHC-Au covalent bonding bridges.

ABSTRACT: Horizontal well drilling and multistage hydraulic fracturing have been widely applied in the Bakken tight oil reservoir to enhance its recovery. However, the primary oil recovery was low due to the majority of oil being remained in the rock matrix. Gas huff-n-puff (HnP), as an enhanced oil recovery (EOR) method, has been applied to the Bakken wells. However, fracture interference among wells leads to fast pressure decline during the gas injection period and slow recovery during the production period. By designing strategies that combine water injection in the offset wells with gas HnP, the pressure of the gas HnP well can be maintained during the production period. Therefore, the effectiveness of gas HnP can potentially be improved. A five-well reservoir model was built using a third-party reservoir simulator with an embedded discrete fracture modeling method. The simulated production data obtained from the reservoir model was successfully matched with the field data. Multiple natural gas HnP strategies were designed and simulated to compare the EOR performances. The results showed that a larger volume of the injected natural gas contributes to more incremental oil production. Higher water injection pressure provided better pressure containment for the gas HnP well, but high water cut presented a detrimental effect on oil production. 1. INTRODUCTION The Bakken Formation has witnessed a boost in oil production since 2008. By the end of March 2022, the oil production of the Bakken region was approximately 1.2 million barrels per day (U.S. Energy Information Administration, 2022). Although the Bakken formation is tight with ultra-low reservoir permeability, the applications of horizontal well drilling and multi-stage hydraulic fracturing have contributed to the success of Bakken. A typical Bakken well has 50 stages of hydraulic fractures in the 10,000 ft lateral section. These hydraulic fractures serve as the "channels" that connect the well with the tight Bakken reservoir, thus the oil that was originally locked in the formation could easily flow to the wellbore. The interaction between hydraulic fractures and pre-existing natural fractures also contributes to larger stimulated reservoir volume and promotes incremental oil production (Aoun et al., 2022; Kolawole and Ispas, 2020; Wan et al., 2020a). Currently, the new Bakken wells have an average initial oil production of 1963 barrels per day (U.S. Energy Information Administration, 2022). With the current oil price of $115 per barrel, a new well could generate an average revenue of $225,745 per day. Despite a large amount of oil that has been produced, the oil recovery of the Bakken Formation remains close to 10% (Hoffman and Evans, 2016). Alternative enhanced oil recovery (EOR) strategies are needed to fully recover the shale oil locked in the tight reservoir matrix.

We report the crystal structures of four different neutral lanthanide (Ln = La, Nd, Eu and Gd) metal–organic frameworks based on the organic linker 2,6-naphthalenedicarboxylate (NDC). The materials are three-dimensional and crystallize in three distinct topologies, with distinct bonding modes of NDC and lanthanide coordination numbers ranging from seven to nine and varying geometry. We denote our materials SLUG-49 [La6(NDC)9(DMF)3·6 DMF], -50 [Nd2(NDC)3O(DMF)2], -51 [Eu2(NDC)3(DMF)2·DMF], and -52 [Gd4(NDC)6(DMF)4] (DMF = N,N-dimethylformamide). The structures exhibit similar thermal decomposition profiles and infrared spectra. The Eu(III)-based material exhibits a sharp red-orange luminescence at 613 nm with a quantum efficiency of 3.56%.

Organolead halide crystalline materials are an emerging class of high-performance photocatalysts. However, limited studies have been performed to tune their photoactive properties by precise introduction of transition metals. Herein, we report the successful incorporation of four different transition metal centers (Mn2+, Co2+, Ni2+ and Zn2+) into a lead oxyhalide crystalline matrix via isoreticular synthesis. Importantly, the precise control of the incoming transition metal positions has been achieved by its octahedral coordination with three organic ligands. Among them, the Zn2+-incorporated material exhibits the highest catalytic activity and recyclable activity in benzylamine oxidation under UV light, which is probably ascribed to the long carrier lifetime and efficient carrier transfer.

Organolead halide perovskites are an emerging class of intrinsic self-trapped broadband emitters, but suffer from lead toxicity and stability problems. Herein, we report a series of metal-organic frameworks (MOFs) based on 0-D zinc halide secondary building units (SBUs), which emit large Stokes shifted broadband bluish-white light. A variety of photophysics studies demonstrate that the broadband emission probably originates from self-trapped excitons, owing to the structurally deformable SBUs. Among the intrinsic self-trapped emitters, these MOFs are very rare examples that exhibit both long-term environmental stability and contain non-toxic elements. Moreover, the open porosity enables the MOF to serve as a host matrix for encapsulating green-emitting Alq3 molecules, exhibiting cold white-light chromatic coordinates of (0.27,0.36) and a correlated color temperature of 8321 K.

Organolead halide perovskites, primarily regarded as a high-performance semiconducting component in photovoltaics, have excellent optical and charge-transport characteristics that are advantageous for photocatalysis. However, their moisture-sensitive nature largely hinders their application to water splitting. Here we report a semiconductive organolead iodide layered crystalline material ([Pb8I8(H2O)3]8+[–O2C(CH2)4CO2–]4) with a bandgap of ~2.74 eV that demonstrates a high robustness over a wide pH range as well as under aqueous boiling conditions. The Earth-abundant material maintains excellent optical characteristics similar to those of perovskites, and includes suitable band positions, excellent carrier diffusion lengths (up to 1.4 μm) and long carrier lifetimes (up to 1.2 μs). When illuminated by sunlight and combined with trace amounts of a Rh co-catalyst, the hybrid iodoplumbate steadily and efficiently produces stoichiometric amounts of hydrogen and oxygen in a recyclable manner. Our findings extend the excellent optoelectronic properties of organolead halide materials from photovoltaics to photocatalytic water splitting. Despite their promising optical properties, organolead halide perovskites are not frequently used in photocatalysis due to their low stability in water. Here, a long-lasting semiconductive organolead iodide layered crystalline material with the ability to perform overall water splitting is introduced.

Kennelia is a small genus in Tortricidae that is distributed in the Oriental and Palaearctic regions, and its taxonomic position within the subfamily Olethreutinae is controversial. For a comprehensive understanding of the genus, we sequenced the mitogenome of Kennelia xylinana, the type species of Kennelia, and Ancylis unculana, a species of Enarmoniini; analyzed the mitogenome characteristics of K. xylinana; and explored its phylogenetic position. Similar to other members of Lepidoptera, the mitogenome of K. xylinana is 15,762-bp long and consists of 13 protein-coding genes (PCGs), two ribosomal RNA genes, 22 transfer RNA genes, and a noncoding control region. In particular, we found a structure (TATAATTAATAA)

To explore the clinical outcomes of unstimulatedPatients with refractory PCOS who underwent unstimulated IVM-surgery from June 2014 to September 2018 were included in this retrospective cohort study. Matured IVM oocytes were freshly fertilized and subsequently frozen at the blastocyst stage. Frozen-thawed embryo transfer was then conducted according to the desire of patients. Oocytes and embryological outcomes, reproductive outcomes were evaluated. Influencing factors of oocytes and embryological outcomes were analyzed by univariate analysis and multivariate analysis. Receiver operating characteristic curves were used to evaluate the predict value of serum hormone levels for oocytes and embryological outcomes.A total of 93 patients with refractory PCOS who underwent unstimulated IVM-surgery were included in this study.13 patients (13/85, 15.3%) had spontaneous pregnancy and live birth after surgery. 34 patients (34/93, 36.6%) obtained blastocysts and received embryo transfer, of which 13 patients (13/34, 38.2%) eventually achieved live birth by IVM. Higher anti-Mullerian hormone, antral follicle count and basal serum luteinizing hormone (LH) levels were strongly correlated with higher number of oocytes retrieved (Unstimulated IVM-surgery provided the opportunity for both spontaneous pregnancy and assisted reproductive technology. Basal FSH and LH were significantly associated with oocyte maturation rate and blastocyst formation of unstimulated IVM-surgery.

Oocyte maturation is a complex and dynamic process regulated by the coordination of ovarian cells and numerous extraovarian signals. From mammal studies, it is learnt that lipid metabolism provides sufficient energy for morphological and cellular events during folliculogenesis, and numerous lipid metabolites, including cholesterol, lipoproteins, and 14-demethyl-14-dehydrolanosterol, act as steroid hormone precursors and meiotic resumption regulators. Endogenous and exogenous signals, such as gonadotropins, insulin, and cortisol, are the upstream regulators in follicular lipid metabolic homeostasis, forming a complex and dynamic network in which the key factor or pathway that plays the central role is still a mystery. Though lipid metabolites are indispensable, long-term exposure to a high-fat environment will induce irreversible damage to follicular cells and oocyte meiosis. This review specifically describes the transcriptional expression patterns of several lipid metabolism–related genes in human oocytes and granulosa cells during folliculogenesis, illustrating the spatiotemporal lipid metabolic changes in follicles and the role of lipid metabolism in female reproductive capacity. This study aims to elaborate the impact of lipid metabolism on folliculogenesis, thus providing guidance for improving the fertility of obese women and the clinical outcome of assisted reproduction.

To reduce the environmental pollution and introduce new form of energy source, the popularity of harvesting energy from wind is increasing day by day. Wind turbines blades are growing longer, as increasing blade length is one of the best ways to produce more wind energy per turbine. However, longer blades require thicker root at the inboard section to counteract the bending load and this thicker root at the inboard section of the large wind turbine blades lower the blades aerodynamic efficiency. This loss of aerodynamic efficiency prevents these longer wind turbine blades from being fully effective as the cost to benefit ratio increases and less power is generated than the optimal value. Additionally, these long blades use a large amount of material. Longer blades require more support to remain structurally sound, which causes a large increase in mass. This material is hard to break down and decompose, causing them to take up a large amount of space in landfills when the blades are unserviceable or replaced because of damage and stress. To overcome this drawback and maximize the harvested energy from the wind, a novel “Biplane” shape wind turbine blade is proposed by the researchers which replaced the monoplane inboard section of the traditional wind turbine blades with the biplane inboard section. This new concept allows to design and manufacture longer wind turbine blade without any loose in aerodynamic efficiency and structural integrity. Biplane wind turbine blades have shown very interesting and promising characteristics in terms of both aerodynamics and structural performance. This new type of wind turbine blade can ensure more power, better aerodynamics efficiency, structural integrity along with lower manufacturing and transportation cost. Previous research conducted found the significant effect of gap and stagger in the aerodynamic performance of biplane blades. However, another very important parameter “pitch angle & decalage” that can improve the aerodynamic performance of biplane wind turbine blades remains unchecked. Keeping that in mind, the current research performed a detailed computational fluid dynamic (CFD) based analysis to find out the pitch angle & decalage effect in biplane wind turbine blade design. Our current research revealed that, apart from the contribution of gap and stagger, the effect of pitch angle & decalage can be significant. At a 6° angle of attack, with both top and bottom blade aerofoil pitch angle setup at positive (+ve) 3° which means decalage is 0°, can improve the lift coefficient (Cl) and the lift to drag ratio (Cl/Cd) or aerodynamics efficiency raised around 48% higher while gap to chord ratio (g/c) and stagger to chord ratio (s/c) were kept 0.5 and 0.25 respectively obtained from the previous state of art.

Attention bias (ABs) to threat is essential in the etiology and maintenance of test anxiety. However, little is known about the attention pattern of ABs in test anxiety. The stimulus duration affects the attention pattern in anxiety. Thus, the present research combined the dot-probe paradigm and event-related potentials (ERPs) and varied the stimulus duration (100 ms or 500 ms) to test the ABs in test anxiety. Consequently, both groups showed a threat N2pc in 100 ms and 500 ms duration, suggesting that both groups allocated attention to the test-related threat. However, in the 100 ms duration, the high test-anxious (HTA) group had smaller target-elicited P1 and greater target-elicited N2 in the threat-congruent condition than in the neutral condition. In the 500 ms duration, an earlier threat N2pc and a threat PD followed a greater target P1, and smaller target N2 were pronounced in the HTA group. The current results provided electrophysiological evidence that the HTA group kept a dynamic attention pattern that fluctuated shift between vigilance and avoidance in the 100 ms and 500 ms duration. The HTA group was more vigilant than the LTA group in the 500 ms duration when strategic attention was concerned, proposing that vigilance in test anxiety was not an automatic process.

Organolead halide materials have shown promising optoelectronic properties that are suitable for light-emitting diodes (e.g., strong photoluminescence, narrow emission width, and high charge carrier mobility). However, the vast majority of them have no open porosity or open metal sites for host-guest interactions and are therefore not widely applicable in intrinsic fluorescent sensing of small molecules. Herein, we report a lead chloride-based metal-organic framework (MOF) with high porosity and stability and promising photoluminescent characteristics, performing as a sensitive, selective, and long-term stable fluorescence probe for NH

We report the structures of six anionic, isomorphous metal–organic frameworks [Ln(bpdc)2–][NH2(CH3)2+], where Ln = La, Ce, Nd, Eu, Gd, Er, and bpdc2– = biphenyl-4,4′-dicarboxylate = –O2C(C6H4)2CO2–...

Ultrafine gold nanoclusters (Au-NCs) are susceptible to migrate and aggregate, even in the porosity of many crystalline solids. N-heterocyclic carbenes (NHCs) are a class of structurally diverse ligands for the stabilization of Au-NCs in homogeneous chemistry, showing catalytic reactivity in CO

The use of in vitro maturation (IVM) before gynecological operation (OP-IVM) is an extension of conventional IVM that combines IVM following oocyte retrieval with routine gynecological surgery. OP-IVM is suitable for patients undergoing benign gynecological surgery who have the need for fertility preservation (FP) or infertility treatments such as in vitro fertilization and embryo transfer (IVF-ET). In the operating room, patients undergoing benign gynecological surgery are first anesthetized and receive ultrasound-guided immature follicle aspiration (IMFA) treatment. As the subsequent gynecological surgery is performed, the cumulus-oocyte complexes (COCs) are examined, and the immature COCs are transferred into the IVM medium and cultured for 28-32 hours in the IVF laboratory. After assessment, mature oocytes in the MII stage will be selected and cryopreserved in liquid nitrogen for FP or fertilized by intracytoplasmic sperm injection (ICSI) for IVF-ET. By combining IVM with gynecological surgery, immature oocytes that would have been discarded can be saved and used for assisted reproductive technology (ART). The procedure, significance and critical aspects of OP-IVM are described in this article.

Species of the genus Syntozyga Lower, 1901 (Lepidoptera, Tortricidae, Olethreutinae) from China are studied. Syntozyga apicispinatasp. nov. and S. similispirographasp. nov. are described, S. pedias (Meyrick, 1920) is recorded for the first time from China, and S. spirographa (Diakonoff, 1968) is newly recorded from the Chinese mainland. Adults and genitalia are illustrated, and a distribution map of the Chinese species is given. Keys to identify the Chinese species of Syntozyga are provided. Species of the genus are well clustered in a neighbor-joining tree based on the sequence data of the COI gene. COI sequences corresponding to the new species and S. spirographa (Diakonoff, 1968) are submitted to BOLD.

Metal-organic frameworks (MOFs) with low-dimensional, deformable haloplumbate secondary building units (SBUs) are an emerging class of intrinsic white-light emitters combining advantageous properties of both MOFs and lead perovskites. Herein, we have successfully synthesized two MOFs with haloplumbate SBUs occupying an extremely high degree of structural strain with local zigzag Pb-X-Pb-X (X = Cl/Br) connectivity located in single-stranded helices. Thus, the electron-phonon coupling in the deformable SBUs affords intrinsic white-light emission and moderately high external photoluminescence quantum efficiencies of 12-15%, superior to our previously reported MOFs. Moreover, the excellent photocarrier diffusion properties of lead perovskites have been successfully incorporated into the MOFs with high chemical robustness in moisture (up to 90% relative humidity, RH).

Metal–organic frameworks (MOFs) are an emerging class of heterogeneous electrocatalyst, though the focus for the vast majority of them has been on employing them as a precursor for carbon materials or as a host material for encapsulating catalytically active species. Herein, we report the preparation of a metal–organic nanosheet with one-dimensional (1-D) [Co4(OH)2]6+ chains via delamination of a 3-D MOF. The resultant atomically thin nanosheets are highly active, robust, and recyclable oxygen evolution reaction (OER) electrocatalysts with a low overpotential 318 mV (without iR compensation) to achieve a current density of 10 mA cm–2. These values along with the small Tafel slope (54 mV dec–1) exhibit a superior performance to the bulk MOF precursor and the benchmark RuO2 catalyst under the identical condition. The electrochemical studies ascribe the excellent OER activity to the high surface area, accessible CoII sites, and good charge transfer of the nanosheets.

Hierarchical ZnO/NiO microstructures with different morphologies were synthesized employing bimetallic Zn/Ni MOFs as the precursor. The MOFs with rambutan- and seaweed-like morphologies were produced using terephthalic acid and polyvinylpyrrolidone. The molar ratio of Zn/Ni plays an important role for the microstructure and capacitance performance of samples. In particular, hierarchical ZnO/NiO hollow microspheres and seaweed microflowers were obtained when the molar ratio of Zn/Ni was 1:2 and 1:1, respectively. The seaweed microflowers exhibited larger specific capacitance and higher rate capability. The composition and unique microstructure result in improved ionic and electronic conductivity and rich electroactive sites for the electrochemical reactions.

In vitro maturation (IVM), the maturation in culture of immature oocytes, has been used in clinic for more than 20 years. Although IVM has the specific advantages of low cost and minor side effects over controlled ovarian stimulation, the prevalence of IVM is less than 1% of routine in vitro fertilization and embryo transfer techniques in many reproductive centers. In this review, we searched the MEDLINE database for all full texts and/or abstract articles published in English with content related to oocyte IVM mainly between 2000 and 2016. Many different aspects of the IVM method may influence oocyte potential, including priming, gonadotrophin, growth factors, and culture times. The culture conditions of IVM result in alterations in the oocyte or cumulus cell transcriptome that are not observed under in vivo culture conditions. Additionally, epigenetic modifications, such as DNA methylation or acetylation, are also different between in vitro and in vivo cultured oocytes. In sum, current IVM technique is still not popular and requires more systematic and intensive research to improve its effects and applications. This review will help point our problems, supply evidence or clues for future improving IVM technique, thus assist patients for fertility treatment or preservation as an additional option.

Few studies have evaluated Hedgehog (Hh) signaling pathway activation in different types of ovarian tumors including benign, borderline and malignant ovarian tumors. The present study investigated the expression of Hh signaling pathway components (SHH, SMO, PTCH, and GLI1) in 193 ovarian epithelial tumor specimens (including 147 malignant epithelial ovarian cancers, 30 borderline ovarian tumors, 16 benign ovarian epithelial tumors) and 11 normal ovarian epithelial tissues by immunohistochemistry. The results demonstrated widespread expression of Hh pathway molecules in ovarian tumors. However, there was no significant difference in the expression intensity of SHH among the four groups (P>0.05). Statistically significant differences were identified in the expression intensity of the SMO, PICH and GLI1 among groups (P