Hierarchically Structured Nb_(2)O_5 Microflowers with Enhanced Capacity and Fast-Charging Capability for Flexible Planar Sodium Ion Micro-Supercapacitors

Planar Na ion micro-supercapacitors(NIMSCs) that offer both high energy density and power density are deemed to a promising class of miniaturized power sources for wearable and portable microelectron-ics. Nevertheless, the development of NIMSCs are hugely impeded by the low capacity and sluggish Na ion kinetics in the negative electrode.Herein, we demonstrate a novel carbon-coated Nb_(2)O_5 microflower with a hierarchical structure composed of vertically intercrossed and porous nanosheets, boosting Na ion storage performance. The unique structural merits, including uniform carbon coating, ultrathin nanosheets and abun-dant pores, endow the Nb_(2)O_5 microflower with highly reversible Na ion storage capacity of 245 mAh g^(-1) at 0.25 C and excellent rate capability.Benefiting from high capacity and fast charging of Nb_(2)O_5 microflower, the planar NIMSCs consisted of Nb_(2)O_5 negative electrode and activated car-bon positive electrode deliver high areal energy density of 60.7 μWh cm^(-2),considerable voltage window of 3.5 V and extraordinary cyclability. Therefore, this work exploits a structural design strategy towards electrode materials for application in NIMSCs, holding great promise for flexible microelectronics.

Importance of oxygen-containing functionalities and pore structures of biochar in catalyzing pyrolysis of homologous poplar

Biochar and bio-oil are produced simultaneously in one pyrolysis process,and they inevitably contact and may interact,influencing the composition of bio-oil and modifying the structure of biochar.In this sense,biochar is an inherent catalyst for pyrolysis.In this study,in order to investigate the influence of functionalities and pore structures of biochar on its capability for catalyzing the conversion of homologous volatiles in bio-oil,three char catalysts(600C,800C,and 800AC)produced via pyrolysis of poplar wood at 600 or 800℃or activated at 800℃,were used for catalyzing pyrolysis of homologous poplar wood at 600℃,respectively.The results indicated that the 600C catalyst was more active than 800C and 800AC for catalyzing cracking of volatiles to form more gas(yield increase by 40.2%)and aromatization of volatiles to form more light or heavy phenolics,due to its abundant oxygen-containing functionalities acting as active sites.The developed pores of the 800AC showed no such catalytic effect but could trap some volatiles and allow their further conversion via sufficient aromatization.Nevertheless,the interaction with the volatiles consumed oxygen on 600C(decrease by 50%),enhancing the aromatic degree and increasing thermal stability.The dominance of deposition of carbonaceous material of a very aromatic nature over 800C and 800AC resulted in net weight gain and blocked micropores but formed additional macropores.The in situ diffuse reflectance infrared Fourier transform spectroscopy characterization of the catalytic pyrolysis indicated superior activity of 600C for removal of -OH,while conversion of the intermediates bearing C=O was enhanced over all the char catalysts.

Covalent Organic Framework with 3D Ordered Channel and Multi-Functional Groups Endows Zn Anode with Superior Stability

Achieving a highly robust zinc(Zn)metal anode is extremely important for improving the performance of aqueous Zn-ion batteries(AZIBs)for advancing“carbon neutrality”society,which is hampered by the uncontrollable growth of Zn dendrite and severe side reactions including hydrogen evolution reaction,corrosion,and passivation,etc.Herein,an interlayer containing fluorinated zincophilic covalent organic framework with sulfonic acid groups(COF-S-F)is developed on Zn metal(Zn@COF-S-F)as the artificial solid electrolyte interface(SEI).Sulfonic acid group(-SO_(3)H)in COF-S-F can effectively ameliorate the desolvation process of hydrated Zn ions,and the three-dimensional channel with fluoride group(-F)can provide interconnected channels for the favorable transport of Zn ions with ion-confinement effects,endowing Zn@COF-S-F with dendrite-free morphology and suppressed side reactions.Consequently,Zn@COF-S-F symmetric cell can stably cycle for 1,000 h with low average hysteresis voltage(50.5 m V)at the current density of 1.5 m A cm^(-2).Zn@COF-S-F|Mn O_(2)cell delivers the discharge specific capacity of 206.8 m Ah g^(-1)at the current density of 1.2 A g^(-1)after 800 cycles with high-capacity retention(87.9%).Enlightening,building artificial SEI on metallic Zn surface with targeted design has been proved as the effective strategy to foster the practical application of high-performance AZIBs.

Revisiting aluminum current collector in lithium-ion batteries:Corrosion and countermeasures

With the large-scale service of lithium-ion batteries(LIBs),their failures have attracted significant attentions.While the decay of active materials is the primary cause for LIB failures,the degradation of auxiliary materials,such as current collector corrosion,should not be disregarded.Therefore,it is necessary to conduct a comprehensive review in this field.In this review,from the perspectives of electrochemistry and materials,we systematically summarize the corrosion behavior of aluminum cathode current collector and propose corresponding countermeasures.Firstly,the corrosion type is clarified based on the properties of passivation layers in different organic electrolyte components.Furthermore,a thoroughgoing analysis is presented to examine the impact of various factors on aluminum corrosion,including lithium salts,organic solvents,water impurities,and operating conditions.Subsequently,strategies for electrolyte and protection layer employed to suppress corrosion are discussed in detail.Lastly and most importantly,we provide insights and recommendations to prevent corrosion of current collectors,facilitate the development of advanced current collectors and the implementation of next-generation high-voltage stable LIBs.

Multistate transition and coupled solid-liquid modeling of motion process of long-runout landslide

The recognition,repetition and prediction of the post-failure motion process of long-runout landslides are key scientific problems in the prevention and mitigation of geological disasters.In this study,a new numerical method involving LPF3D based on a multialgorithm and multiconstitutive model was proposed to simulate long-runout landslides with high precision and efficiency.The following results were obtained:(a)The motion process of landslides showed a steric effect with mobility,including gradual disintegration and spreading.The sliding mass can be divided into three states(dense,dilute and ultradilute)in the motion process,which can be solved by three dynamic regimes(friction,collision,and inertial);(b)Coupling simulation between the solid grain and liquid phases was achieved,focusing on drag force influences;(c)Different algorithms and constitutive models were employed in phase-state simulations.The volume fraction is an important indicator to distinguish different state types and solid‒liquid ratios.The flume experimental results were favorably validated against long-runout landslide case data;and(d)In this method,matched dynamic numerical modeling was developed to better capture the realistic motion process of long-runout landslides,and the advantages of continuum media and discrete media were combined to improve the computational accuracy and efficiency.This new method can reflect the realistic physical and mechanical processes in long-runout landslide motion and provide a suitable method for risk assessment and pre-failure prediction.

A VGGNet-based correction for satellite altimetry-derived gravity anomalies to improve the accuracy of bathymetry to depths of 6500 m

Understanding the topographic patterns of the seafloor is a very important part of understanding our planet.Although the science involved in bathymetric surveying has advanced much over the decades,less than 20%of the seafloor has been precisely modeled to date,and there is an urgent need to improve the accuracy and reduce the uncertainty of underwater survey data.In this study,we introduce a pretrained visual geometry group network(VGGNet)method based on deep learning.To apply this method,we input gravity anomaly data derived from ship measurements and satellite altimetry into the model and correct the latter,which has a larger spatial coverage,based on the former,which is considered the true value and is more accurate.After obtaining the corrected high-precision gravity model,it is inverted to the corresponding bathymetric model by applying the gravity-depth correlation.We choose four data pairs collected from different environments,i.e.,the Southern Ocean,Pacific Ocean,Atlantic Ocean and Caribbean Sea,to evaluate the topographic correction results of the model.The experiments show that the coefficient of determination(R~2)reaches 0.834 among the results of the four experimental groups,signifying a high correlation.The standard deviation and normalized root mean square error are also evaluated,and the accuracy of their performance improved by up to 24.2%compared with similar research done in recent years.The evaluation of the R^(2) values at different water depths shows that our model can achieve performance results above 0.90 at certain water depths and can also significantly improve results from mid-water depths when compared to previous research.Finally,the bathymetry corrected by our model is able to show an accuracy improvement level of more than 21%within 1%of the total water depths,which is sufficient to prove that the VGGNet-based method has the ability to perform a gravity-bathymetry correction and achieve outstanding results.

Advanced Design of Soft Robots with Artificial Intelligence

In recent years,breakthrough has been made in the field of artificial intelligence(AI),which has also revolutionized the industry of robotics.Soft robots featured with high-level safety,less weight,lower power consumption have always been one of the research hotspots.Recently,multifunctional sensors for perception of soft robotics have been rapidly developed,while more algorithms and models of machine learning with high accuracy have been optimized and proposed.Designs of soft robots with AI have also been advanced ranging from multimodal sensing,human-machine interaction to effective actuation in robotic systems.Nonethe-less,comprehensive reviews concerning the new developments and strategies for the ingenious design of the soft robotic systems equipped with AI are rare.Here,the new development is systematically reviewed in the field of soft robots with AI.First,background and mechanisms of soft robotic systems are briefed,after which development focused on how to endow the soft robots with AI,including the aspects of feeling,thought and reaction,is illustrated.Next,applications of soft robots with AI are systematically summarized and discussed together with advanced strategies proposed for performance enhancement.Design thoughts for future intelligent soft robotics are pointed out.Finally,some perspectives are put forward.

Polyphenol components in black chokeberry(Aronia melanocarpa)as clinically proven diseases control factors——an overview

The black chokeberry is rich in polyphenols,including flavonoids with anthocyanins,flavanols and lavonols as the main components and a variety of phenolic acids represented by chlorogenic acid.Because of these polyphenols,black chokeberry has the effect of preventing and adjuvant therapy diseases.This study summarized the current research results on the types and contents of functional components in black chokeberry,and analyzed their digestion,absorption and metabolism in human body.On this basis,the disease control functions that have been proved effective in clinical research were reviewed and analyzed.These studies showed that black chokeberry have good prevention and adjuvant therapy effects on hyperlipidemia,hypertension,diabetes and inflammation.Because there are different functional components in black chokeberry,its prevention and treatment of the same disease can come from multiple pathways,which provides a more reliable effectiveness for the disease control of different populations.

A peak enhancement of frequency response of waveguide integrated silicon-based germanium avalanche photodetector

Avalanche photodetectors(APDs) featuring an avalanche multiplication region are vital for reaching high sensitivity and responsivity in optical transceivers. Waveguide-coupled Ge-on-Si separate absorption, charge, and multiplication(SACM)APDs are popular due to their straightforward fabrication process, low optical propagation loss, and high detection sensitivity in optical communications. This paper introduces a lateral SACM Ge-on-Si APD on a silicon-on-insulator(SOI) wafer, featuring a 10 μm-long, 0.5 μm-wide Ge layer at 1310 nm on a standard 8-inch silicon photonics platform. The dark current measures approximately 38.6 μA at-21 V, indicating a breakdown voltage greater than-21 V for the device. The APDs exhibit a unitgain responsivity of 0.5 A/W at-10 V. At-15 V, their responsivity reaches 2.98 and 2.91 A/W with input powers of-10 and-25 dBm, respectively. The device's 3-dB bandwidth is 15 GHz with an input power of-15 dBm and a gain is 11.68. Experimental results show a peak in impedance at high bias voltages, attributed to inductor and capacitor(LC) circuit resonance, enhancing frequency response. Furthermore, 20 Gbps eye diagrams at-21 V and-9 dBm input power reveal signal to noise ratio(SNRs) of 5.30. This lateral SACM APD, compatible with the stand complementary metal oxide semiconductor(CMOS) process,shows that utilizing the peaking effect at low optical power increases bandwidth.

Deep Learning-Based Secure Transmission Strategy with Sensor-Transmission-Computing Linkage for Power Internet of Things

The automatic collection of power grid situation information, along with real-time multimedia interaction between the front and back ends during the accident handling process, has generated a massive amount of power grid data. While wireless communication offers a convenient channel for grid terminal access and data transmission, it is important to note that the bandwidth of wireless communication is limited. Additionally, the broadcast nature of wireless transmission raises concerns about the potential for unauthorized eavesdropping during data transmission. To address these challenges and achieve reliable, secure, and real-time transmission of power grid data, an intelligent security transmission strategy with sensor-transmission-computing linkage is proposed in this paper. The primary objective of this strategy is to maximize the confidentiality capacity of the system. To tackle this, an optimization problem is formulated, taking into consideration interruption probability and interception probability as constraints. To efficiently solve this optimization problem, a low-complexity algorithm rooted in deep reinforcement learning is designed, which aims to derive a suboptimal solution for the problem at hand. Ultimately, through simulation results, the validity of the proposed strategy in guaranteed communication security, stability, and timeliness is substantiated. The results confirm that the proposed intelligent security transmission strategy significantly contributes to the safeguarding of communication integrity, system stability, and timely data delivery.

Effect of screening colonoscopy frequency on colorectal cancer mortality in patients with a family history of colorectal cancer

BACKGROUND Colorectal cancer is a common malignant tumor in China,and its incidence in the elderly is increasing annually.Inflammatory bowel disease is a group of chronic non-specific intestinal inflammatory diseases,including ulcerative colitis and Crohn’s disease.We included the clinicopathological and follow-up data of patients with colorectal cancer who underwent laparoscopic colectomy or open colectomy at our Gastrointestinal Department between January 2019 and December 2022.Surgical indicators,oncological indicators,and survival rates were compared between the groups.The results of 104 patients who met the above criteria were extracted from the database(laparoscopic colectomy group=63,open colectomy group=41),and there were no statistically significant differences in the baseline data or follow-up time between the two groups.RESULTS Intraoperative blood loss,time to first ambulation,and time to first fluid intake were significantly lower in the laparoscopic colectomy group than in the open colectomy group.The differences in overall mortality,tumor-related mortality,and recurrence rates between the two groups were not statistically significant,and survival analysis showed that the differences in the cumulative overall survival,tumor-related survival,and cumulative recurrence-free rates between the two groups were not statistically significant.CONCLUSION In elderly patients with colorectal cancer,laparoscopic colectomy has better short-term outcomes than open colectomy,and laparoscopic colectomy has superior long-term survival outcomes compared with open colectomy.

Geostructures, dynamics and risk mitigation of high-altitude and long- runout rockslides

Long-runout rockslides at high altitude could cause disaster chain in river basins and destroy towns and major infrasturctures.This paper firstly explores the initiation mechanism of high-altitude and long-runout rockslides.Two types of sliding-prone geostructure models,i.e.the fault control type in orogenic belt and the fold control type in platform area,are proposed.Then,large-scale experimental apparatus and associated numerical simulations are conducted to understanding the chain-style dynamics of rockslide-debris avalanche-debris flow.The results reveal the fragmentation effects,the rheological behaviors and the boundary layer effect of long-runout avalanche-debris flow.The dynamic character-istics of quasi-static-transition-inertia state and solid-liquid coupling in rapid movement of rockslide-debris avalanche-debris flow are investigated.Finally,the risk mitigation strategy of the non-structure and structure for resilient energy dissipation are illustrated for initiation,transition and deposition zones.The structural prevention and mitigation methods have been successfully applied to the high-altitude and long-runout rockslides in Zhouqu and Maoxian of the Wenchuan earthquake zone,as well as the other major geohazards in Qinghai-Tibet Plateau and its adjacent areas.

Tracklet-to-object Matching for Climbing Starlink Satellites through Recursive Orbit Determination and Prediction

Concerns for the collision risk involving Starlink satellites have motivated the interest in obtaining their accurate orbit knowledge.However,accurate orbit determination(OD)and prediction(OP)of Starlink satellites confront two main challenges:mismatching or missed matching of sparse tracklets to maneuvering satellites,and unknown or unmodeled orbit maneuvers.How to exactly associate a tracklet to the right satellite is the primary issue,since a maneuvering satellite does not follow the naturally evolving orbit during the maneuvering,while more tracklets are needed for developing an accurate orbit maneuver model.If these two challenges are not well addressed,it may lead to catalog maintenance failure or even loss of objects.This paper proposes a method to correctly match tracklets to the climbing Starlink satellites.It is based on the recursive OD and OP,in which the orbit maneuver is modeled and the thrust is estimated,such that the subsequent OP accuracy guarantees the correct match of tracklets shortly after the OD time.Experiments with climbing Starlink satellites demonstrate that the tracklets within three days of the last TLE(two-line element)are all correctly matched to the right satellites.With the matched tracklets,the thrust accelerations of climbing Starlink satellites can be precisely estimated through an orbit control approach,and the position prediction accuracy over 48 hours is at the level of a few kilometers,providing accurate orbit knowledge for reliable collision warning involving Starlink satellites.

Characteristics and dynamic analysis of the February 2021 long-runout disaster chain triggered by massive rock and ice avalanche at Chamoli, Indian Himalaya

A massive rock and ice avalanche occurred on the western slope of the Ronti Gad valley in the northern part of Chamoli,Indian Himalaya,on 7 February 7,2021.The avalanche on the high mountain slope at an elevation of 5600 m above sea level triggered a long runout disaster chain,including rock mass avalanche,debris avalanche,and flood.The disaster chain had a horizontal travel distance of larger than 17,600 m and an elevation difference of 4300 m.In this study,the disaster characteristics and dynamic process were analyzed by multitemporal satellite imagery.The results show that the massive rock and ice avalanche was caused by four large expanding discontinuity planes.The disaster chain was divided into five zones by satellite images and field observation,including source zone,transition zone,dynamic entrainment zone,flow deposition zone,and flood zone.The entrainment effect and melting water were recognized as the main causes of the long-runout distance.Based on the seismic wave records and field videos,the time progress of the disaster was analyzed and the velocity of frontal debris at different stages was calculated.The total analyzed disaster duration was 1247 s,and the frontal debris velocity colliding with the second hydropower station was approximately 23 m/s.This study also carried out the numerical simulation of the disaster by rapid mass movement simulation(RAMMS).The numerical results reproduced the dynamic process of the debris avalanche,and the mechanism of long-runout avalanche was further verified by parametric study.Furthermore,this study discussed the potential causes of disaster and flood and the roles of satellite images and seismic networks in the monitoring and early-warning.

Pterostilbene antagonizes homocysteine-induced oxidative stress,apoptosis and lipid deposition in vascular endothelial cells

Hyperhomocysteinemia(HHcy)causes oxidative stress, induces apoptosis, and leads to damage to the vascular endothelium is the starting point of atherosclerosis. Pterostilbene(Pte)has been reported to have antioxidant and anti-apoptotic effects under various pathological conditions. The purpose of this study was to explore whether Pte can inhibit the oxidative stress and apoptosis of vascular endothelium induced by homocysteine(Hcy)and to explain the possible mechanism by which it occurs. The results showed that 20 μmol/L Pte significantly reduced the accumulation of reactive oxygen species, malondialdehyde, and lipids in cells induced by Hcy and promoted the activities of superoxide dismutase and catalase. The Hoechst 33342/PI staining assay showed that Pte antagonized Hcy-induced apoptosis. Pte inhibited Hcy-induced Akt dephosphorylation, increased p53, and decreased the Bcl-2/Bax ratio and caspase-9/caspase-3 activation in a dose-dependent manner. LY294002 pretreatment partially reversed the protective effect of Pte by blocking the PI3K/Akt pathway. Moreover, Pte reduced lipid deposition in human umbilical vein endothelial cells(HUVECs). This study proposes that Pte can inhibit Hcy-induced oxidative stress and apoptosis of HUVECs, and the PI3K/Akt/p53 signaling pathway of apoptosis was revealed. These results suggest that Pte exhibits significant potential for dealing with HHcy-induced vascular endothelial injury, such as atherosclerosis.

Lonicera caerulea polyphenols inhibit fat absorption by regulating Nrf2-ARE pathway mediated epithelial barrier dysfunction and special microbiota

Scope:High-fat diet(HFD)induces imbalance in the small intestine environment,where fat digestion and absorption mainly take place.This study aimed to elucidate the mechanisms by which Lonicera caerulea polyphenols(LCP)might inhibit fat absorption,from the perspective of small intestine microbiota and epithelial barrier integrity.Methods and results:Male Sprague-Dawley rats were given HFD with or without co-administration of LCP for 8 weeks.The results showed that LCP supplementation significantly decreased the levels of serum triglycerides(TG),total cholesterol(TC),and low-density lipoprotein cholesterol(LDL-C),and increased the contents of fecal sterols,in HFD rats.LCP also inhibited the dysfunction of the small intestine epithelial barrier,via alleviating the oxidative stress activated by Nrf2-ARE pathway,and by modulating the expressions of pro-inflammatory factors such as tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),cyclooxygenase-2(COX-2),nuclear factor kappa-B p65(NF-κB p65)and inducible nitric oxide synthase(iNOS)in the small intestine.Additionally,LCP administration restored the balance in small intestine microbiota and increased the abundance of the specific bacteria,such as Lactobacillus,involved in fat absorption.Conclusion:Our results demonstrated that LCP may be beneficial to inhibit fat absorption.The mechanism seems to be associated with the protection of the epithelial barrier integrity and the modulation of specific bacteria in the small intestine.

Effect of dual targeting procyanidins nanoparticles on metabolomics of lipopolysaccharide-stimulated inflammatory macrophages

Inflammation plays an important role in the occurrence and development of many inflammatory diseases.The purpose of this study was to evaluate the anti-inflammatory effect and metabolic behavior of the dual targeting procyanidins(PC)nanoparticles on lipopolysaccharide(LPS)-stimulated inflammatory macrophages by metabolomics method.The double-targeting PC nanoparticles could specifi cally target both the CD44 receptor and mitochondria,while the single targeting PC-loaded nanoparticles that could target the CD44 receptor on the surface of macrophages.The double-targeting PC nanoparticles had better inhibitory effect than single-targeting PC nanoparticles on the leakage of lactate dehydrogenase and reactive oxygen species overexpression induced by LPS.Amino acid metabolism,energy metabolism and purine metabolism were disordered in LPS-treated group,and metabolic pathway analysis indicated that the double-targeting PC nanoparticles reversed some of LPS impacts.The changes of these potential biomarkers and their corresponding pathways are helpful to further understand the mechanism of PC nanoparticles in alleviating inflammation,and promote their application in nutrition intervention.

Efficacy of continuous gastric artery infusion chemotherapy in relieving digestive obstruction in advanced gastric cancer

BACKGROUND Obstruction or fullness after feeding is common in gastric cancer(GC)patients,affecting their nutritional status and quality of life.Patients with digestive obstruction are generally in a more advanced stage.Existing methods,including palliative gastrectomy,gastrojejunostomy,endoluminal stent,jejunal nutrition tube and intravenous chemotherapy,have limitations in treating these symptoms.AIM To analyze the efficacy of continuous gastric artery infusion chemotherapy(cGAIC)in relieving digestive obstruction in patients with advanced GC.METHODS This study was a retrospective study.Twenty-nine patients with digestive obstruction of advanced GC who underwent at least one cycle of treatment were reviewed at The Second Affiliated Hospital of Zhejiang University School of Medicine.The oxaliplatin-based intra-arterial infusion regimen was applied in all patients.Mild systemic chemotherapy was used in combination with local treatment.The clinical response was evaluated by contrast-enhanced computed tomography using Response Evaluation Criteria In Solid Tumors(RECIST)criteria.Digestive tract symptoms and toxic effects were analyzed regularly.A comparison of the Karnofsky Performance Status(KPS)score and Stooler’s Dysphagia Score before and after therapy was made.Univariate survival analysis and multivariate survival analysis were also performed to explore the key factors affecting patient survival.RESULTS All patients finished cGAIC successfully without microcatheter displacement,as confirmed by arteriography.The median follow-up time was 24 mo(95%CI:20.24-27.76 mo).The overall response rate was 89.7%after cGAIC according to the RECIST criteria.The postoperative Stooler’s Dysphagia Score was significantly improved.Twentytwo(75.9%)of the 29 patients experienced relief of digestive obstruction after the first two cycles,and 13(44.8%)initially unresectable patients were then considered radically resectable.The median overall survival time(mOS)was 16 mo(95%CI:9.32-22.68 mo).Patients who received radical surgery had a significantly longer mOS than other patients(P value<0.001).Multivariate Cox regression analysis indicated that radical resection after cGAIC,intravenous chemotherapy after cGAIC,and immunotherapy after cGAIC were independent predictors of mOS.None of the patients stopped treatment because of adverse events.CONCLUSION cGAIC was effective and safe in relieving digestive obstruction in advanced GC,and it could improve surgical conversion possibility and survival time.

Load Profile Analysis for Mitigating Load-Shedding in Central Africa: Case of Kinshasa

Load shedding is a major problem in Central Africa, with negative consequences for both society and the economy. However, load profile analysis can help to alleviate this problem by providing valuable information about consumer demand. This information can be used by power utilities to forecast and reduce power cuts effectively. In this study, the direct method was used to create load profiles for residential feeders in Kinshasa. The results showed that load shedding on weekends results in significant financial losses and changes in people’s behavior. In November 2022 alone, load shedding was responsible for $ 23,4 08,984 and $ 2 80,9 07,808 for all year in losses. The study also found that the SAIDI index for the southern direction of the Kinshasa distribution network was 122.49 hours per feeder, on average. This means that each feeder experienced an average of 5 days of load shedding in November 2022. The SAIFI index was 20 interruptions per feeder, on average, and the CAIDI index was 6 hours, on average, before power was restored. This study also proposes ten strategies for the reduction of load shedding in the Kinshasa and central Africa power distribution network and for the improvement of its reliability, namely: Improved load forecasting, Improvement of the grid infrastructure, Scheduling of load shedding, Demand management programs, Energy efficiency initiatives, Distributed Generation, Automation and Monitoring of the Grid, Education and engagement of the consumer, Policy and regulatory assistance, and Updated load profile analysis.

Design and feasibility analysis of a new completion monitoring technical scheme for natural gas hydrate production tests

As a prerequisite and a guarantee for safe and efficient natural gas hydrates(NGHs)exploitation,it is imperative to effectively determine the mechanical properties of NGHs reservoirs and clarify the law of the change in the mechanical properties with the dissociation of NGHs during NGHs production tests by depressurization.Based on the development of Japan’s two offshore NGHs production tests in vertical wells,this study innovatively proposed a new subsea communication technology-accurate directional connection using a wet-mate connector.This helps to overcome the technical barrier to the communication between the upper and lower completion of offshore wells.Using this new communication technology,this study explored and designed a mechanical monitoring scheme for lower completion(sand screens).This scheme can be used to monitor the tensile stress and radial compressive stress of sand screens caused by NGHs reservoirs in real time,thus promoting the technical development for the rapid assessment and real-time feedback of the in-situ mechanical response of NGHs reservoirs during offshore NGHs production tests by depressurization.