In 2022,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results.First,a series of well-defined dinuclear organoboron catalysts were develo...In 2022,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results.First,a series of well-defined dinuclear organoboron catalysts were developed to precisely control the enchainment of ether and carbonate segments during the copolymerization of CO_(2)and epoxides.Second,polyester had been synthesized through cationic copolymerization of cyclic anhydride.Third,ring-opening polymerization of carbon dioxide based valerolactone had been achieved,revealing the prospect of 3-ethylidene-6-vinyltetrahydro-2H-pyran-2-one(EVL)in utilizing CO_(2)and synthesizing functional polymers.Fourth,machine learning methods have been applied to biomaterial research,enabling high-throughput screening of functional biomaterial surfaces for implantable devices,and searching for potent antimicrobial peptides in whole combinatorial peptide libraries.Fifth,methods of characterization of biomacromolecule RNA transcription and manipulation of nucleoside modification were developed.Sixth,artificial enzymes-armed Bifidobacterium Longum probiotics were established to tune down gut inflammation.Seventh,three-dimensional(3D)printing technologies were used to engineer tough supramolecular hydrogels.Eighth,hydroplastic foaming graphene frameworks for acoustic and conductive polymer composites were provided for application.Ninth,aggregate photophysics about the nature of through-space interactions(TSIs)and manipulating their strength in small molecules with non-conjugated structure had been elucidated.Tenth,the forming mechanism of a newfound nested texture in poly(L-lactic acid)(PLLA)spherulitic films had been revealed.Finally,the isotropically dyeing mechanism of KDP single crystals grown from hydrogels have been explored.The related works are reviewed in this paper.展开更多
In 2023,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results in the five research directions.First,for controllable catalytic polymeriz...In 2023,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results in the five research directions.First,for controllable catalytic polymerization,a new silicon-centered organoboron binary catalyst was developed for copolymerization of epoxides,and a series of cooperative organocatalysts were proposed for ring-opening copolymerization of chalcogen-rich monomers.Second,with respect to microstructure and rheology,axially encoded metafiber demonstrated its capacity for integrating multiple electronics,while artificial nacre materials showed improved strength and toughness due to interlayer entanglement.Third,concerning separating functional polymers,interfacial polymerization was monitored via aggregation-induced emission,and vacuum filtration was applied to assist interfacial polymerization.Fourth,in terms of biomedical functional polymers,we designed antibacterial materials such as a novel quaternary ammonium salt that enables polyethylene terephthalate recycling and its antibacterial function,nanozyme-armed phage proved its efficiency in combating bacterial infection,and also transition metal nanoparticles showed capacities in antibacterial treatments.We also made achievements in biomedical materials,including polymeric microneedles for minimally invasive implantation and functionalization of cardiac patches,as well as ROSresponsive/scavenging prodrug/miRNA balloon coating to promote drug delivery efficiency.Besides,methods and mechanisms of RNA labeling has been developed.Fifth,about photo-electro-magnetic functional polymers,through-space conjugation was successfully manipulated by altering subunit packing modes,room-temperature phosphorescent hydrogels were synthesized via polymerization-induced crystallization of dopant molecules,and single crystals of both fullerene and non-fullerene acceptors were grown in crystallized organogel,with their photodetection performance further explored.The related works are reviewed in this paper.展开更多
Objective To investigate the serum total IgE （tlgE） and specific IgE （slgE） to common allergens among allergic patients in Guangzhou, China. Methods 7 085 patients were examined for tlgE and slgE to 15 allergens, ...Objective To investigate the serum total IgE （tlgE） and specific IgE （slgE） to common allergens among allergic patients in Guangzhou, China. Methods 7 085 patients were examined for tlgE and slgE to 15 allergens, based on the protocols of reversed enzyme allergosorbent test and the sandwich enzyme-linked immunosorbent assay. Results 3 758 （53.04%） patients tested positive for tlgE, and 4 640 （65.49%） for slgE. Der pteronyssinus, Derfarinae, eggs, and cow＇s milk were the most common allergens leading to higher positive rates of slgE responses. Several peaks of sensitization were： Der pteronyssinus, Derfarinae, and Blomia tropicalis at age 10-12; cow＇s milk at age below 3; eggs at age 4-6. The mean level and positive rate of tlgE tended to increase in subjects sensitized to more allergens. Sensitization to Der pteronyssinus （OR, 1.6; P〈O.05）, Der farinae （OR, 1.5; P〈O.05）, Blomia tropicalis （OR, 1.4; P〈O.05）, Blattella germanica （OR, 1.5; P〈O.05）, cow＇s milk （OR, 1.3; P〈O.05）, and soy beans （OR, 2.0; P〈O.05） were independently correlated with allergy-related conditions in preliminary diagnosis. Conclusion The major allergens in Guangzhou include Derpteronyssinus, Derfarinae, cow＇s milk, and eggs. Sensitization to these allergens appears to be predictors of allergy-related disorder.展开更多
In 2020, the MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had made progresses in several aspects. First, a series of metal-free organoboron catalysts had been designed an...In 2020, the MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had made progresses in several aspects. First, a series of metal-free organoboron catalysts had been designed and synthesized facilely, exhibiting outstanding reactivity, thermalstability and productivity in different kinds of polymerization and cycloaddition reactions. Second, a variety of chalcogen(O, S, Se)-rich polymers had been synthesized via organocatalysis and fabricated to be the ionic conductive and photoluminescent materials. Third, diverse microenvironment-sensitive nanoparticles had been designed,and novel strategies had been realized, to enhance the therapeutic efficacy in cancer as well as biofilmassociated infections. Fourth, m6 A modification on cellular transcriptome-wide messenger RNA had been successfully mapped at single base resolution using a metabolic labeling method. Fifth, a hydrogel-based robot had been developed, showing swift locomotion as a response to dynamic light stimulations. Sixth,the conformation-size scaling law and the conformation evolution map of 2 D macromolecules in solution had been elucidated experimentally, in the single-layer graphene oxide model. Seventh, semitransparent polymer solar cells, promising as building-integrated photovoltaics, have been developed with the fine balance among power conversion efficiency, visible light transparency and infrared photon radiation rejection. Finally, long-range ordered bulk-heterojunctions of organic semiconductors had been achieved,and their superior optoelectronic properties and potential application in photoelectric conversion had been revealed. The related work progresses are reviewed in this paper.展开更多
In 2021,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results.First,a series of versatile organoboron catalysts were synthesized for rin...In 2021,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results.First,a series of versatile organoboron catalysts were synthesized for ring-opening(co)polymerizations.Second,a catalyst-free polycondensation mechanism was proposed for the production of polyesters with high molecular weights.Third,a co-assembly method that can fabricate films and coatings with controllable structures and properties on various substrates was demonstrated,providing a platform for the construction of novel surface coatings.Forth,facile methods for producing high-productivity poly(propylene carbonate)and semicrystalline polyester have been discovered.And linear non-conjugated polyesters exhibiting yellow-green clusteroluminescence were developed for the first time.Fifth,a supramolecular prodrug nano-assembly strategy has been developed for reactive nitrogen species potentiated chemotherapy.Sixth,a series of tough and stiff supramolecular hydrogels with shape memory properties have been used for information encryption.Seventh,reversible fusion and fission of wet-spun graphene oxide fibers has been successfully achieved.Eighth,three non-conjugated polypeptides were synthesized and the mechanism of clusteroluminescence was studied.Ninth,a series of conducting covalent organic frameworks with high electrical conductivity and carrier mobility have been used as high-performance chemiresistor,electrocatalyst,and organic field-effect transistor.Tenth,the exploration of non-fused electron acceptors,and their photostable mechanism are exemplified for developing high-performance,low-cost and eco-friendly polymer solar cells.Finally,gel-grown long-range ordering bulk-heterojunctions has achieved improved X-ray detector performance.展开更多
In recent years,the usage,management and benefit of large-scale scientific research instruments and equipment in scientific research institutes have been a leading issue in the management of scientific research instit...In recent years,the usage,management and benefit of large-scale scientific research instruments and equipment in scientific research institutes have been a leading issue in the management of scientific research institutes.Within the scope of equipment budget,it is necessary for each equipment acquisition team to conduct a round of communication,coordination and negotiation with suppliers in order to improve the cost performance of equipment procurement and maximize the performance index to meet the needs of scientific research.By introducing the practical experience of the State Key Laboratory in purchasing imported equipment and managing large-scale instruments,this paper probes into the management process of the imported large-scale scientific research tax-free equipment of scientific research institutes,and explores the system and methods to guarantee and improve the efficiency of large-scale instruments in scientific research institutes from the aspects of policy,funds and technology.展开更多
The State Key Laboratory of Natural and Biomimetic Drugs was approved for a funding of nearly 100 million yuan specifically aimed at the purchase and maintenance of equipment and instruments from 2018 to 2020,which is...The State Key Laboratory of Natural and Biomimetic Drugs was approved for a funding of nearly 100 million yuan specifically aimed at the purchase and maintenance of equipment and instruments from 2018 to 2020,which is a record high.The Laboratory focuses on two major directions of scientific research,the"basic scientific problems of drug resistance of complex components of natural products"and the"key biomimetic scientific problems of endogenous substances therapeutic functions".The selection of scientific instruments and equipment,trial production,upgrading,as well as high level of technical and management personnel allocation and other aspects are critical to meet the development needs of the Key Laboratory and to maintain the advantages and leading role in these two major directions of scientific research.展开更多
The Key Laboratory of Drinking Water Science and Technology(DWST),a key branch of the Laboratory of Environmental Aquatic Chemistry,has been staying on the cutting edge in the field of drinking water since its establi...The Key Laboratory of Drinking Water Science and Technology(DWST),a key branch of the Laboratory of Environmental Aquatic Chemistry,has been staying on the cutting edge in the field of drinking water since its establishment in 2014.The main goal of this laboratory is to ensure drinking water safety,particularly with regard to public health.To achieve this goal,the research teams have been making great efforts to develop water quality criteria and standards for health risk control;establish stateof-the-art theoretical and technological systems for pollution control and water purification;form an innovation layout from foundation to application,from engineering to management,and from water source to tap;and provide systematic solutions to forward-looking and universal scientific problems in drinking water safety.The laboratory mainly focuses on four research fields:(1)methodology for water quality risk assessment;(2)combined pollution of water source and ecological restoration;(3)new theories and technologies for water purification;and(4)chemical/biological processes and regulations of water distribution systems.展开更多
The Key Laboratory of Coastal Wetland Biogeosciences (KLCWB) was established in August 2012 and is incorporated into the Qingdao Institute of Marine Geology, China Geological Survey, Ministry of Natural Resources. The...The Key Laboratory of Coastal Wetland Biogeosciences (KLCWB) was established in August 2012 and is incorporated into the Qingdao Institute of Marine Geology, China Geological Survey, Ministry of Natural Resources. The KLCWB focus on the frontiers of international coastal wetland biogeology science and technology development, especially the hot topics in biological geology, environmental geology and ecological resources.展开更多
This year marks the tenth anniversary of the State Key Laboratory of Advanced Displays and Optoelectronics Technologies(SKLADOT)at the Hong Kong University of Science and Technology(HKUST).The predecessor of SKLADOT w...This year marks the tenth anniversary of the State Key Laboratory of Advanced Displays and Optoelectronics Technologies(SKLADOT)at the Hong Kong University of Science and Technology(HKUST).The predecessor of SKLADOT was the Center for Display Research(CDR)which was started in 1995.Thus display research has a long history at HKUST.展开更多
·Prof.XIONG,could you please give us a brief introduction to SKLMCMS？Director XIONG Ke：The State Key Laboratory of Mechanics and Control of Mechanical Structures（SKLMCMS）was established with the approval of t...·Prof.XIONG,could you please give us a brief introduction to SKLMCMS？Director XIONG Ke：The State Key Laboratory of Mechanics and Control of Mechanical Structures（SKLMCMS）was established with the approval of the Ministry of Science and Technology of the People’s Republic of China in October 2011.The laboratory is located at Nanjing University of Aeronautics and Astronautics（NUAA）.展开更多
The loaded rock experiences multiple stages of deformation.It starts with the formation of microcracks at low stresses(crack initiation,CI)and then transitions into unstable crack propagation(crack damage,CD)near the ...The loaded rock experiences multiple stages of deformation.It starts with the formation of microcracks at low stresses(crack initiation,CI)and then transitions into unstable crack propagation(crack damage,CD)near the ultimate strength.In this study,both the acoustic emission method(AEM)and the ultrasonic testing method(UTM)were used to examine the characteristics of AE parameters(b-value,peak frequency,frequency-band energy ratio,and fractal dimension)and ultrasonic(ULT)properties(velocity,amplitude,energy attenuation,and scattering attenuation)of bedded shale at CI,CD,and ultimate strength.The comparison involved analyzing the strain-based method(SBM),AEM,and UTM to determine the thresholds for damage stress.A fuzzy comprehensive evaluation model(FCEM)was created to describe the damage thresholds and hazard assessment.The results indicate that the optimal AE and ULT parameters for identifying CI and CD stress are ringing count,ultrasonic amplitude,energy attenuation,and scattering attenuation of the S-wave.Besides,damage thresholds were detected earlier by AE monitoring,ranging from 3 MPa to 10 MPa.CI and CD identified by UTM occurred later than SBM and AEM,and were in the range of 12 MPa.The b-value,peak frequency,energy ratio in the low-frequency band(0e62.5 kHz),correlation dimension,and sandbox dimension showed low values at the peak stress,while the energy ratio in a moderate-frequency band(187.5e281.25 kHz)and amplitude showed high values.The successful application of FCEM to laboratory testing of shales has demonstrated its ability to quantitatively identify AE/ULT precursors of seismic hazards associated with rock failure.展开更多
Current research on heterogeneous advanced oxidation processes(HAOPs)predominantly emphasizes catalyst iteration and innovation.Significant efforts have been made to regulate the electron structure and optimize the el...Current research on heterogeneous advanced oxidation processes(HAOPs)predominantly emphasizes catalyst iteration and innovation.Significant efforts have been made to regulate the electron structure and optimize the electron distribution,thereby increasing the catalytic activity.However,this focus often overshadows an equally essential aspect of HAOPs:the adsorption effect.Adsorption is a critical initiator for triggering the interaction of oxidants and contaminants with heterogeneous catalysts.The efficacy of these interactions is influenced by a variety of physicochemical properties,including surface chemistry and pore sizes,which determine the affinities between contaminants and material surfaces.This dispar ity in affinity is pivotal because it underpins the selective removal of contaminants,especially in complex waste streams containing diverse contaminants and competing matrices.Consequently,understanding and mastering these interfacial interactions is fundamentally indispensable not only for improving pro cess efficiency but also for enhancing the selectivity of contaminant removal.Herein,we highlight the importance of adsorption-driven interfacial interactions for fundamentally elucidating the catalytic mechanisms of HAOPs.Such interactions dictate the overall performance of the treatment processes by balancing the adsorption,reaction,and desorption rates on the catalyst surfaces.Elucidating the adsorption effect not only shifts the paradigm in understanding HAOPs but also improves their practical ity in water treatment and wastewater decontamination.Overall,we propose that revisiting adsorption driven interfacial interactions holds great promise for optimizing catalytic processes to develop effective HAOP strategies.展开更多
Gas content serves as a critical indicator for assessing the resource potential of deep coal mines and forecasting coal mine gas outburst risks.However,existing sampling technologies face challenges in maintaining the...Gas content serves as a critical indicator for assessing the resource potential of deep coal mines and forecasting coal mine gas outburst risks.However,existing sampling technologies face challenges in maintaining the integrity of gas content within samples and are often constrained by estimation errors inherent in empirical formulas,which results in inaccurate gas content measurements.This study introduces a lightweight,in-situ pressure-and gas-preserved corer designed to collect coal samples under the pressure conditions at the sampling point,effectively preventing gas loss during transfer and significantly improving measurement accuracy.Additionally,a gas migration model for deep coal mines was developed to elucidate gas migration characteristics under pressure-preserved coring conditions.The model offers valuable insights for optimizing coring parameters,demonstrating that both minimizing the coring hole diameter and reducing the pressure difference between the coring-point pressure and the original pore pressure can effectively improve the precision of gas content measurements.Coring tests conducted at an experimental base validated the performance of the corer and its effectiveness in sample collection.Furthermore,successful horizontal coring tests conducted in an underground coal mine roadway demonstrated that the measured gas content using pressure-preserved coring was 34%higher than that obtained through open sampling methods.展开更多
Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning paradigm.While this approach allows models to specialize in speci...Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning paradigm.While this approach allows models to specialize in specific tasks with reduced training costs,the substantial memory requirements during fine-tuning present a barrier to broader deployment.Parameter-Efficient Fine-Tuning(PEFT)techniques,such as Low-Rank Adaptation(LoRA),and parameter quantization methods have emerged as solutions to address these challenges by optimizing memory usage and computational efficiency.Among these,QLoRA,which combines PEFT and quantization,has demonstrated notable success in reducing memory footprints during fine-tuning,prompting the development of various QLoRA variants.Despite these advancements,the quantitative impact of key variables on the fine-tuning performance of quantized LLMs remains underexplored.This study presents a comprehensive analysis of these key variables,focusing on their influence across different layer types and depths within LLM architectures.Our investigation uncovers several critical findings:(1)Larger layers,such as MLP layers,can maintain performance despite reductions in adapter rank,while smaller layers,like self-attention layers,aremore sensitive to such changes;(2)The effectiveness of balancing factors depends more on specific values rather than layer type or depth;(3)In quantization-aware fine-tuning,larger layers can effectively utilize smaller adapters,whereas smaller layers struggle to do so.These insights suggest that layer type is a more significant determinant of fine-tuning success than layer depth when optimizing quantized LLMs.Moreover,for the same discount of trainable parameters,reducing the trainable parameters in a larger layer is more effective in preserving fine-tuning accuracy than in a smaller one.This study provides valuable guidance for more efficient fine-tuning strategies and opens avenues for further research into optimizing LLM fine-tuning in resource-constrained environments.展开更多
Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in c...Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate models.Previous studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC simulations.In this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its collapse.Through a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s variability.The traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of AMOC.The results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter slowly.However,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale.展开更多
【Objectives】Si and microbial application could relieve the crop replanting problems(CRPs).We further studied the change of key microorganisms that are related to the beneficial effects,aiming at provide reference fo...【Objectives】Si and microbial application could relieve the crop replanting problems(CRPs).We further studied the change of key microorganisms that are related to the beneficial effects,aiming at provide reference for the manufacture and application of both microbial agents and Si fertilizer in food lily production.【Methods】A field experiment was conducted over a three-year period,from March 2019 to March 2022.The experimental field had been continuously cultivated with lily for 9 years.Three treatments were established:silicon fertilizer(SF),microbial agents(“Special 8^(TM)”,MF),and combined application of silicon fertilizer and microbial agents(SMF).A control group with blank soil(CK)was also included.At seedling stage of Lanzhou lilies in 2020 and 2021,the shoot and bulb dry weight,and the plant height and stem diameter of Lanzhou lilies were investigated for calculation of seedling index.In July 2020,20 plants were selected in each plot,and root zone soils were sampled at a depth of 20 cm,10 cm away from the roots,and then mixed to form a composite sample.The soil available Si and organic matter content were analyzed,and the fungal community structure and some specific microbial groups in soils were determined with high-throughput sequencing of ITS.【Results】All the three treatments significantly enhanced the lily plant growth and the seedling index,compared to CK.Besides,SF and MF treatments increased the relative abundances(RA)and diversity of fungal communities,and altered the community structures.The RA of some specific groups were found to be significantly correlated with the seedling index and/or soil available Si.Of them,the RA of the genera Fusarium,Dactylonectria,Humicola,Stilbella,and the species Humicola_grisea showed a positive correlation,while that of the genera Mortierella,Stilbella,Holtermanniella,and the species Mortierella_fatshederae showed a negative correlation with seedling index.The genera Fusarium,Stilbella,the species Humicola_grisea,and Dactylonectria_estremocensis showed a positive correlation,while the genura Stilbella,and the species Mortierella fatshederae showed a negative correlation with available Si content.In the co-occurence network of top twenty fungal genera and top sixteen bacterial genera(RA>0.2%),Holtermanniella was the only genus that interacted with the bacteria and negatively correlated with bacterial genus Blastococcus.Holtermanniella was also the most densely connected genera,followed by the genus Fusarium,Didymella and Humicola.In addition,the genus Holtermanniella was the key species connecting fungal and bacterial community in soil.Fungal functional prediction revealed that SF,MF and SMF treatments decreased plant pathogens guilds and increased the beneficial guilds Ectomycorrhizal,plant saprophyte,leaf saprophyte,and arbuscular mycorrhizal compared to CK.【Conclusions】Combined application of silicon fertilizer and microbial agents can alleviate continuous replanting problems of Lanzhou lilies through restoring the fungal community diversity,and promoting plant residue depredation,thus reducing soil born disease incidence.The beneficial genus Humicola and its one species H.grisea acts as bioconversion,and the genus Acremonium acts as plant pathogen inhibitor.展开更多
Layered rock masses represent complex geological formations commonly encountered in the surrounding rock of deep engineering excavations(Hou et al.,2019;Xu et al.,2017;Yang C H et al.,2009;Xian and Tan,1989).These roc...Layered rock masses represent complex geological formations commonly encountered in the surrounding rock of deep engineering excavations(Hou et al.,2019;Xu et al.,2017;Yang C H et al.,2009;Xian and Tan,1989).These rock masses are predominantly composed of sedimentary,para-metamorphic,and volcanic rock types,characterized by a set of prominent,primary bedding structural planes(layers)exhibiting relatively consistent orientations and significant spatial continuity.展开更多
The Chinese Society of Clinical Oncology Non-small Cell Lung Cancer(CSCO NSCLC)guidelines were first published in 2016,ranking among the earliest-released guidelines within the CSCO series.In 2020 the CSCO published s...The Chinese Society of Clinical Oncology Non-small Cell Lung Cancer(CSCO NSCLC)guidelines were first published in 2016,ranking among the earliest-released guidelines within the CSCO series.In 2020 the CSCO published separate guidelines for NSCLC and small cell lung cancer(SCLC)for the first time to improve clinical usability.展开更多
Medium-high maturity continental shale oil is one of the hydrocarbon resources with the most potential for successful development in China.Nevertheless,the unique geological conditions of a multi-lithologic superposit...Medium-high maturity continental shale oil is one of the hydrocarbon resources with the most potential for successful development in China.Nevertheless,the unique geological conditions of a multi-lithologic superposition shield the vertical propagation of hydraulic fractures and limit the longitudinal reconstruction in reservoirs,posing a great challenge for large-scale volumetric fracturing.Radial wellbore crosslayer fracturing,which transforms the interaction between the hydraulic fractures and lithologic interface into longitudinal multilayer competitive initiation,could provide a potential solution for this engineering challenge.To determine the longitudinal propagation behaviors of fractures guided by radial wellbores,true triaxial fracturing experiments were performed on multilayer shale-sandstone samples,with a focus on the injection pressure response,fracture morphology,and cross-layer pattern.The effects of the radial borehole length L,vertical stress difference K_(v),injection rate Q,and viscosity m of the fracturing fluid were analyzed.The results indicate that radial wellbores can greatly facilitate fracture initiation and cross-layer propagation.Unlike conventional hydraulic fracturing,there are two distinct fracture propagation patterns in radial wellbore fracturing:cross-layering and skip-layering.The fracture height guided by a radial wellbore is positively correlated with K_(v),Q,and m.Increasing these parameters causes a shift in the fracture initiation from a single root to an asynchronous root/toe end and can improve the cross-layer propagation capacity.Critical parameter thresholds exist for fracture propagation through and across interlayers under the guidance of radial boreholes.A parameter combination of critical cross-layering/skip-layering or alternating displacement/viscosity is recommended to simultaneously improve the fracture height and degree of lateral activation.The degree of correlation of different parameters with the vertical fracture height can be written as L>Q/m>K_(v).Increasing the radial wellbore length can effectively facilitate fracture cross-/skip-layer propagation and reduce the critical threshold of injection parameters,which is conducive to maximizing the stimulated reservoir volume.展开更多
基金the support from the SCI-TECH Academy of Zhejiang University。
文摘In 2022,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results.First,a series of well-defined dinuclear organoboron catalysts were developed to precisely control the enchainment of ether and carbonate segments during the copolymerization of CO_(2)and epoxides.Second,polyester had been synthesized through cationic copolymerization of cyclic anhydride.Third,ring-opening polymerization of carbon dioxide based valerolactone had been achieved,revealing the prospect of 3-ethylidene-6-vinyltetrahydro-2H-pyran-2-one(EVL)in utilizing CO_(2)and synthesizing functional polymers.Fourth,machine learning methods have been applied to biomaterial research,enabling high-throughput screening of functional biomaterial surfaces for implantable devices,and searching for potent antimicrobial peptides in whole combinatorial peptide libraries.Fifth,methods of characterization of biomacromolecule RNA transcription and manipulation of nucleoside modification were developed.Sixth,artificial enzymes-armed Bifidobacterium Longum probiotics were established to tune down gut inflammation.Seventh,three-dimensional(3D)printing technologies were used to engineer tough supramolecular hydrogels.Eighth,hydroplastic foaming graphene frameworks for acoustic and conductive polymer composites were provided for application.Ninth,aggregate photophysics about the nature of through-space interactions(TSIs)and manipulating their strength in small molecules with non-conjugated structure had been elucidated.Tenth,the forming mechanism of a newfound nested texture in poly(L-lactic acid)(PLLA)spherulitic films had been revealed.Finally,the isotropically dyeing mechanism of KDP single crystals grown from hydrogels have been explored.The related works are reviewed in this paper.
基金the support from the SCI-TECH Academy of Zhejiang University。
文摘In 2023,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results in the five research directions.First,for controllable catalytic polymerization,a new silicon-centered organoboron binary catalyst was developed for copolymerization of epoxides,and a series of cooperative organocatalysts were proposed for ring-opening copolymerization of chalcogen-rich monomers.Second,with respect to microstructure and rheology,axially encoded metafiber demonstrated its capacity for integrating multiple electronics,while artificial nacre materials showed improved strength and toughness due to interlayer entanglement.Third,concerning separating functional polymers,interfacial polymerization was monitored via aggregation-induced emission,and vacuum filtration was applied to assist interfacial polymerization.Fourth,in terms of biomedical functional polymers,we designed antibacterial materials such as a novel quaternary ammonium salt that enables polyethylene terephthalate recycling and its antibacterial function,nanozyme-armed phage proved its efficiency in combating bacterial infection,and also transition metal nanoparticles showed capacities in antibacterial treatments.We also made achievements in biomedical materials,including polymeric microneedles for minimally invasive implantation and functionalization of cardiac patches,as well as ROSresponsive/scavenging prodrug/miRNA balloon coating to promote drug delivery efficiency.Besides,methods and mechanisms of RNA labeling has been developed.Fifth,about photo-electro-magnetic functional polymers,through-space conjugation was successfully manipulated by altering subunit packing modes,room-temperature phosphorescent hydrogels were synthesized via polymerization-induced crystallization of dopant molecules,and single crystals of both fullerene and non-fullerene acceptors were grown in crystallized organogel,with their photodetection performance further explored.The related works are reviewed in this paper.
基金supported by Guangdong Industry Technology and Development Fund(No.2011B061200040)Science Foundation of Guangzhou Medical Univesity(Project No.2013A06)Guangdong Natural Science Foundation(No.S2013010014728)
文摘Objective To investigate the serum total IgE （tlgE） and specific IgE （slgE） to common allergens among allergic patients in Guangzhou, China. Methods 7 085 patients were examined for tlgE and slgE to 15 allergens, based on the protocols of reversed enzyme allergosorbent test and the sandwich enzyme-linked immunosorbent assay. Results 3 758 （53.04%） patients tested positive for tlgE, and 4 640 （65.49%） for slgE. Der pteronyssinus, Derfarinae, eggs, and cow＇s milk were the most common allergens leading to higher positive rates of slgE responses. Several peaks of sensitization were： Der pteronyssinus, Derfarinae, and Blomia tropicalis at age 10-12; cow＇s milk at age below 3; eggs at age 4-6. The mean level and positive rate of tlgE tended to increase in subjects sensitized to more allergens. Sensitization to Der pteronyssinus （OR, 1.6; P〈O.05）, Der farinae （OR, 1.5; P〈O.05）, Blomia tropicalis （OR, 1.4; P〈O.05）, Blattella germanica （OR, 1.5; P〈O.05）, cow＇s milk （OR, 1.3; P〈O.05）, and soy beans （OR, 2.0; P〈O.05） were independently correlated with allergy-related conditions in preliminary diagnosis. Conclusion The major allergens in Guangzhou include Derpteronyssinus, Derfarinae, cow＇s milk, and eggs. Sensitization to these allergens appears to be predictors of allergy-related disorder.
基金support from the SCI-TECH Academy of Zhejiang University。
文摘In 2020, the MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had made progresses in several aspects. First, a series of metal-free organoboron catalysts had been designed and synthesized facilely, exhibiting outstanding reactivity, thermalstability and productivity in different kinds of polymerization and cycloaddition reactions. Second, a variety of chalcogen(O, S, Se)-rich polymers had been synthesized via organocatalysis and fabricated to be the ionic conductive and photoluminescent materials. Third, diverse microenvironment-sensitive nanoparticles had been designed,and novel strategies had been realized, to enhance the therapeutic efficacy in cancer as well as biofilmassociated infections. Fourth, m6 A modification on cellular transcriptome-wide messenger RNA had been successfully mapped at single base resolution using a metabolic labeling method. Fifth, a hydrogel-based robot had been developed, showing swift locomotion as a response to dynamic light stimulations. Sixth,the conformation-size scaling law and the conformation evolution map of 2 D macromolecules in solution had been elucidated experimentally, in the single-layer graphene oxide model. Seventh, semitransparent polymer solar cells, promising as building-integrated photovoltaics, have been developed with the fine balance among power conversion efficiency, visible light transparency and infrared photon radiation rejection. Finally, long-range ordered bulk-heterojunctions of organic semiconductors had been achieved,and their superior optoelectronic properties and potential application in photoelectric conversion had been revealed. The related work progresses are reviewed in this paper.
基金the support from the SCI-TECH Academy of Zhejiang University。
文摘In 2021,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results.First,a series of versatile organoboron catalysts were synthesized for ring-opening(co)polymerizations.Second,a catalyst-free polycondensation mechanism was proposed for the production of polyesters with high molecular weights.Third,a co-assembly method that can fabricate films and coatings with controllable structures and properties on various substrates was demonstrated,providing a platform for the construction of novel surface coatings.Forth,facile methods for producing high-productivity poly(propylene carbonate)and semicrystalline polyester have been discovered.And linear non-conjugated polyesters exhibiting yellow-green clusteroluminescence were developed for the first time.Fifth,a supramolecular prodrug nano-assembly strategy has been developed for reactive nitrogen species potentiated chemotherapy.Sixth,a series of tough and stiff supramolecular hydrogels with shape memory properties have been used for information encryption.Seventh,reversible fusion and fission of wet-spun graphene oxide fibers has been successfully achieved.Eighth,three non-conjugated polypeptides were synthesized and the mechanism of clusteroluminescence was studied.Ninth,a series of conducting covalent organic frameworks with high electrical conductivity and carrier mobility have been used as high-performance chemiresistor,electrocatalyst,and organic field-effect transistor.Tenth,the exploration of non-fused electron acceptors,and their photostable mechanism are exemplified for developing high-performance,low-cost and eco-friendly polymer solar cells.Finally,gel-grown long-range ordering bulk-heterojunctions has achieved improved X-ray detector performance.
文摘In recent years,the usage,management and benefit of large-scale scientific research instruments and equipment in scientific research institutes have been a leading issue in the management of scientific research institutes.Within the scope of equipment budget,it is necessary for each equipment acquisition team to conduct a round of communication,coordination and negotiation with suppliers in order to improve the cost performance of equipment procurement and maximize the performance index to meet the needs of scientific research.By introducing the practical experience of the State Key Laboratory in purchasing imported equipment and managing large-scale instruments,this paper probes into the management process of the imported large-scale scientific research tax-free equipment of scientific research institutes,and explores the system and methods to guarantee and improve the efficiency of large-scale instruments in scientific research institutes from the aspects of policy,funds and technology.
文摘The State Key Laboratory of Natural and Biomimetic Drugs was approved for a funding of nearly 100 million yuan specifically aimed at the purchase and maintenance of equipment and instruments from 2018 to 2020,which is a record high.The Laboratory focuses on two major directions of scientific research,the"basic scientific problems of drug resistance of complex components of natural products"and the"key biomimetic scientific problems of endogenous substances therapeutic functions".The selection of scientific instruments and equipment,trial production,upgrading,as well as high level of technical and management personnel allocation and other aspects are critical to meet the development needs of the Key Laboratory and to maintain the advantages and leading role in these two major directions of scientific research.
文摘The Key Laboratory of Drinking Water Science and Technology(DWST),a key branch of the Laboratory of Environmental Aquatic Chemistry,has been staying on the cutting edge in the field of drinking water since its establishment in 2014.The main goal of this laboratory is to ensure drinking water safety,particularly with regard to public health.To achieve this goal,the research teams have been making great efforts to develop water quality criteria and standards for health risk control;establish stateof-the-art theoretical and technological systems for pollution control and water purification;form an innovation layout from foundation to application,from engineering to management,and from water source to tap;and provide systematic solutions to forward-looking and universal scientific problems in drinking water safety.The laboratory mainly focuses on four research fields:(1)methodology for water quality risk assessment;(2)combined pollution of water source and ecological restoration;(3)new theories and technologies for water purification;and(4)chemical/biological processes and regulations of water distribution systems.
文摘The Key Laboratory of Coastal Wetland Biogeosciences (KLCWB) was established in August 2012 and is incorporated into the Qingdao Institute of Marine Geology, China Geological Survey, Ministry of Natural Resources. The KLCWB focus on the frontiers of international coastal wetland biogeology science and technology development, especially the hot topics in biological geology, environmental geology and ecological resources.
文摘This year marks the tenth anniversary of the State Key Laboratory of Advanced Displays and Optoelectronics Technologies(SKLADOT)at the Hong Kong University of Science and Technology(HKUST).The predecessor of SKLADOT was the Center for Display Research(CDR)which was started in 1995.Thus display research has a long history at HKUST.
文摘·Prof.XIONG,could you please give us a brief introduction to SKLMCMS？Director XIONG Ke：The State Key Laboratory of Mechanics and Control of Mechanical Structures（SKLMCMS）was established with the approval of the Ministry of Science and Technology of the People’s Republic of China in October 2011.The laboratory is located at Nanjing University of Aeronautics and Astronautics（NUAA）.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.U20A20266 and 12302503)Scientific and technological research projects in Sichuan province(Grant No.2024NSFSC0973).
文摘The loaded rock experiences multiple stages of deformation.It starts with the formation of microcracks at low stresses(crack initiation,CI)and then transitions into unstable crack propagation(crack damage,CD)near the ultimate strength.In this study,both the acoustic emission method(AEM)and the ultrasonic testing method(UTM)were used to examine the characteristics of AE parameters(b-value,peak frequency,frequency-band energy ratio,and fractal dimension)and ultrasonic(ULT)properties(velocity,amplitude,energy attenuation,and scattering attenuation)of bedded shale at CI,CD,and ultimate strength.The comparison involved analyzing the strain-based method(SBM),AEM,and UTM to determine the thresholds for damage stress.A fuzzy comprehensive evaluation model(FCEM)was created to describe the damage thresholds and hazard assessment.The results indicate that the optimal AE and ULT parameters for identifying CI and CD stress are ringing count,ultrasonic amplitude,energy attenuation,and scattering attenuation of the S-wave.Besides,damage thresholds were detected earlier by AE monitoring,ranging from 3 MPa to 10 MPa.CI and CD identified by UTM occurred later than SBM and AEM,and were in the range of 12 MPa.The b-value,peak frequency,energy ratio in the low-frequency band(0e62.5 kHz),correlation dimension,and sandbox dimension showed low values at the peak stress,while the energy ratio in a moderate-frequency band(187.5e281.25 kHz)and amplitude showed high values.The successful application of FCEM to laboratory testing of shales has demonstrated its ability to quantitatively identify AE/ULT precursors of seismic hazards associated with rock failure.
基金supported by the National Key Research and Development Program of China(2022YFC3205300)the National Natural Science Foundation of China(22176124).
文摘Current research on heterogeneous advanced oxidation processes(HAOPs)predominantly emphasizes catalyst iteration and innovation.Significant efforts have been made to regulate the electron structure and optimize the electron distribution,thereby increasing the catalytic activity.However,this focus often overshadows an equally essential aspect of HAOPs:the adsorption effect.Adsorption is a critical initiator for triggering the interaction of oxidants and contaminants with heterogeneous catalysts.The efficacy of these interactions is influenced by a variety of physicochemical properties,including surface chemistry and pore sizes,which determine the affinities between contaminants and material surfaces.This dispar ity in affinity is pivotal because it underpins the selective removal of contaminants,especially in complex waste streams containing diverse contaminants and competing matrices.Consequently,understanding and mastering these interfacial interactions is fundamentally indispensable not only for improving pro cess efficiency but also for enhancing the selectivity of contaminant removal.Herein,we highlight the importance of adsorption-driven interfacial interactions for fundamentally elucidating the catalytic mechanisms of HAOPs.Such interactions dictate the overall performance of the treatment processes by balancing the adsorption,reaction,and desorption rates on the catalyst surfaces.Elucidating the adsorption effect not only shifts the paradigm in understanding HAOPs but also improves their practical ity in water treatment and wastewater decontamination.Overall,we propose that revisiting adsorption driven interfacial interactions holds great promise for optimizing catalytic processes to develop effective HAOP strategies.
基金supported by the National Natural Science Foundation of China(Nos.51827901,42477191,and 52304033)the Fundamental Research Funds for the Central Universities(No.YJ202449)+1 种基金the Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences(No.SKLGME022009)the China Postdoctoral Science Foundation(No.2023M742446).
文摘Gas content serves as a critical indicator for assessing the resource potential of deep coal mines and forecasting coal mine gas outburst risks.However,existing sampling technologies face challenges in maintaining the integrity of gas content within samples and are often constrained by estimation errors inherent in empirical formulas,which results in inaccurate gas content measurements.This study introduces a lightweight,in-situ pressure-and gas-preserved corer designed to collect coal samples under the pressure conditions at the sampling point,effectively preventing gas loss during transfer and significantly improving measurement accuracy.Additionally,a gas migration model for deep coal mines was developed to elucidate gas migration characteristics under pressure-preserved coring conditions.The model offers valuable insights for optimizing coring parameters,demonstrating that both minimizing the coring hole diameter and reducing the pressure difference between the coring-point pressure and the original pore pressure can effectively improve the precision of gas content measurements.Coring tests conducted at an experimental base validated the performance of the corer and its effectiveness in sample collection.Furthermore,successful horizontal coring tests conducted in an underground coal mine roadway demonstrated that the measured gas content using pressure-preserved coring was 34%higher than that obtained through open sampling methods.
基金supported by the National Key R&D Program of China(No.2021YFB0301200)National Natural Science Foundation of China(No.62025208).
文摘Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning paradigm.While this approach allows models to specialize in specific tasks with reduced training costs,the substantial memory requirements during fine-tuning present a barrier to broader deployment.Parameter-Efficient Fine-Tuning(PEFT)techniques,such as Low-Rank Adaptation(LoRA),and parameter quantization methods have emerged as solutions to address these challenges by optimizing memory usage and computational efficiency.Among these,QLoRA,which combines PEFT and quantization,has demonstrated notable success in reducing memory footprints during fine-tuning,prompting the development of various QLoRA variants.Despite these advancements,the quantitative impact of key variables on the fine-tuning performance of quantized LLMs remains underexplored.This study presents a comprehensive analysis of these key variables,focusing on their influence across different layer types and depths within LLM architectures.Our investigation uncovers several critical findings:(1)Larger layers,such as MLP layers,can maintain performance despite reductions in adapter rank,while smaller layers,like self-attention layers,aremore sensitive to such changes;(2)The effectiveness of balancing factors depends more on specific values rather than layer type or depth;(3)In quantization-aware fine-tuning,larger layers can effectively utilize smaller adapters,whereas smaller layers struggle to do so.These insights suggest that layer type is a more significant determinant of fine-tuning success than layer depth when optimizing quantized LLMs.Moreover,for the same discount of trainable parameters,reducing the trainable parameters in a larger layer is more effective in preserving fine-tuning accuracy than in a smaller one.This study provides valuable guidance for more efficient fine-tuning strategies and opens avenues for further research into optimizing LLM fine-tuning in resource-constrained environments.
基金supported by the National Key R&D Program of China [grant number 2023YFF0805202]the National Natural Science Foun-dation of China [grant number 42175045]the Strategic Priority Research Program of the Chinese Academy of Sciences [grant number XDB42000000]。
文摘Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate models.Previous studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC simulations.In this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its collapse.Through a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s variability.The traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of AMOC.The results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter slowly.However,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale.
基金Key Research project of Gansu Province of China(22YF7NA108)National Natural Science Foundation of China(31860549)+1 种基金Industry Supporting Project from Education Department of Gansu Province(2023CYZC-49)Major Science and Technology project of Gansu province(24ZDNA006)。
文摘【Objectives】Si and microbial application could relieve the crop replanting problems(CRPs).We further studied the change of key microorganisms that are related to the beneficial effects,aiming at provide reference for the manufacture and application of both microbial agents and Si fertilizer in food lily production.【Methods】A field experiment was conducted over a three-year period,from March 2019 to March 2022.The experimental field had been continuously cultivated with lily for 9 years.Three treatments were established:silicon fertilizer(SF),microbial agents(“Special 8^(TM)”,MF),and combined application of silicon fertilizer and microbial agents(SMF).A control group with blank soil(CK)was also included.At seedling stage of Lanzhou lilies in 2020 and 2021,the shoot and bulb dry weight,and the plant height and stem diameter of Lanzhou lilies were investigated for calculation of seedling index.In July 2020,20 plants were selected in each plot,and root zone soils were sampled at a depth of 20 cm,10 cm away from the roots,and then mixed to form a composite sample.The soil available Si and organic matter content were analyzed,and the fungal community structure and some specific microbial groups in soils were determined with high-throughput sequencing of ITS.【Results】All the three treatments significantly enhanced the lily plant growth and the seedling index,compared to CK.Besides,SF and MF treatments increased the relative abundances(RA)and diversity of fungal communities,and altered the community structures.The RA of some specific groups were found to be significantly correlated with the seedling index and/or soil available Si.Of them,the RA of the genera Fusarium,Dactylonectria,Humicola,Stilbella,and the species Humicola_grisea showed a positive correlation,while that of the genera Mortierella,Stilbella,Holtermanniella,and the species Mortierella_fatshederae showed a negative correlation with seedling index.The genera Fusarium,Stilbella,the species Humicola_grisea,and Dactylonectria_estremocensis showed a positive correlation,while the genura Stilbella,and the species Mortierella fatshederae showed a negative correlation with available Si content.In the co-occurence network of top twenty fungal genera and top sixteen bacterial genera(RA>0.2%),Holtermanniella was the only genus that interacted with the bacteria and negatively correlated with bacterial genus Blastococcus.Holtermanniella was also the most densely connected genera,followed by the genus Fusarium,Didymella and Humicola.In addition,the genus Holtermanniella was the key species connecting fungal and bacterial community in soil.Fungal functional prediction revealed that SF,MF and SMF treatments decreased plant pathogens guilds and increased the beneficial guilds Ectomycorrhizal,plant saprophyte,leaf saprophyte,and arbuscular mycorrhizal compared to CK.【Conclusions】Combined application of silicon fertilizer and microbial agents can alleviate continuous replanting problems of Lanzhou lilies through restoring the fungal community diversity,and promoting plant residue depredation,thus reducing soil born disease incidence.The beneficial genus Humicola and its one species H.grisea acts as bioconversion,and the genus Acremonium acts as plant pathogen inhibitor.
基金supported by the National Natural Science Foundation of China(Nos.42107211 and U23A20651)the Natural Science Foundation of Sichuan Province(No.2025ZNSFSC0097)。
文摘Layered rock masses represent complex geological formations commonly encountered in the surrounding rock of deep engineering excavations(Hou et al.,2019;Xu et al.,2017;Yang C H et al.,2009;Xian and Tan,1989).These rock masses are predominantly composed of sedimentary,para-metamorphic,and volcanic rock types,characterized by a set of prominent,primary bedding structural planes(layers)exhibiting relatively consistent orientations and significant spatial continuity.
文摘The Chinese Society of Clinical Oncology Non-small Cell Lung Cancer(CSCO NSCLC)guidelines were first published in 2016,ranking among the earliest-released guidelines within the CSCO series.In 2020 the CSCO published separate guidelines for NSCLC and small cell lung cancer(SCLC)for the first time to improve clinical usability.
基金supported by the National Natural Science Foun-dation of China(52421002,U24B6001,52204019,and 52192624)the Open Foundation of the Shanxi Key Laboratory of Carbon Dioxide Sequestration and Enhanced Oil Recovery。
文摘Medium-high maturity continental shale oil is one of the hydrocarbon resources with the most potential for successful development in China.Nevertheless,the unique geological conditions of a multi-lithologic superposition shield the vertical propagation of hydraulic fractures and limit the longitudinal reconstruction in reservoirs,posing a great challenge for large-scale volumetric fracturing.Radial wellbore crosslayer fracturing,which transforms the interaction between the hydraulic fractures and lithologic interface into longitudinal multilayer competitive initiation,could provide a potential solution for this engineering challenge.To determine the longitudinal propagation behaviors of fractures guided by radial wellbores,true triaxial fracturing experiments were performed on multilayer shale-sandstone samples,with a focus on the injection pressure response,fracture morphology,and cross-layer pattern.The effects of the radial borehole length L,vertical stress difference K_(v),injection rate Q,and viscosity m of the fracturing fluid were analyzed.The results indicate that radial wellbores can greatly facilitate fracture initiation and cross-layer propagation.Unlike conventional hydraulic fracturing,there are two distinct fracture propagation patterns in radial wellbore fracturing:cross-layering and skip-layering.The fracture height guided by a radial wellbore is positively correlated with K_(v),Q,and m.Increasing these parameters causes a shift in the fracture initiation from a single root to an asynchronous root/toe end and can improve the cross-layer propagation capacity.Critical parameter thresholds exist for fracture propagation through and across interlayers under the guidance of radial boreholes.A parameter combination of critical cross-layering/skip-layering or alternating displacement/viscosity is recommended to simultaneously improve the fracture height and degree of lateral activation.The degree of correlation of different parameters with the vertical fracture height can be written as L>Q/m>K_(v).Increasing the radial wellbore length can effectively facilitate fracture cross-/skip-layer propagation and reduce the critical threshold of injection parameters,which is conducive to maximizing the stimulated reservoir volume.
