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Facile method for creating frustrated Lewis pairs in g-C_(3)N_(4) to enhance photocatalytic nitrogen fixation performance
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作者 Lanxin Wang Kaiwei Liang +2 位作者 Xuelian Yu Guocheng Lv Libing Liao 《Chinese Chemical Letters》 2026年第1期622-625,共4页
The rate-limited activation of N≡N triple bonds with high bond energies has been a bottleneck in photoctalytic nitrogen fixation.Here,polymeric carbon nitride with frustrated Lewis pairs(FLPs) was constructed by inse... The rate-limited activation of N≡N triple bonds with high bond energies has been a bottleneck in photoctalytic nitrogen fixation.Here,polymeric carbon nitride with frustrated Lewis pairs(FLPs) was constructed by inserting electron-deficient magnesium into g-C_(3)N_(4)(CN).The synergistic interactions between Mg and amino groups in CN led to a 7.2 fold increase in the photoreactivity of nitrogen(N_(2)) fixation by carbon nitride. 展开更多
关键词 N_(2)fixation PHOTOCATALYTIC FLPs AMMONIA g-C_(3)N_(4)
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Biological nitrogen and carbon fixation:Bridging the gap between synthetic symbioses and synthetic biology
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作者 Qi Cheng Chukang Ma Xuelu Wang 《The Crop Journal》 2026年第1期74-86,共13页
Biological nitrogen fixation(BNF)and photosynthetic carbon fixation underpin food production and climate mitigation,yet natural systems are constrained by oxygen sensitivity,high energy demand,and inefficient catalyst... Biological nitrogen fixation(BNF)and photosynthetic carbon fixation underpin food production and climate mitigation,yet natural systems are constrained by oxygen sensitivity,high energy demand,and inefficient catalysts.This review synthesizes advances that recast these processes as engineering targets and proposes a conceptual roadmap that bridges synthetic symbioses with the synthetic biology of enzymes and pathways.For BNF,progress spans cross-kingdom strategies—from refactoring nif gene sets and targeting nitrogenase assembly to eukaryotic organelles,to engineering plant-associated diazotrophs,rhizosphere control circuits,and emerging nodule-like microenvironments.For carbon assimilation,new-to-nature CO_(2)-fixation modules and photorespiratory bypasses illustrate how pathway redesign and alternative carboxylases can circumvent key Calvin–Benson–Bassham limitations,and expanding photosynthetic light capture offers additional leverage.Across these domains,we extract common design principles:(i)nitrogenase output is increasingly governed by carbon/energy supply and electron delivery as much as by oxygen protection;(ii)robust function requires compartment-aware enzyme–chassis coordination,substrate channeling,and dynamic regulation using sensors and control circuits;and(iii)scalable implementation may benefit from distributing metabolic labor across engineered consortia rather than forcing all functions into a single host.We discuss enabling technologies—including AI-guided protein design and directed evolution,cell-free prototyping,chassis toolkits,and materials/bioelectrochemical interfaces—that can accelerate design–build–test–learn cycles and reduce barriers to deployment.Together,these insights define a path toward integrated nitrogen and carbon fixation systems for low-emission agriculture and biomanufacturing. 展开更多
关键词 Biological nitrogen fixation Photosynthetic carbon fixation Nitrogenase engineering Non-natural enzymes AI-guided protein design
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Editing a gibberellin receptor gene improves yield and nitrogen fixation in soybean
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作者 Jiajun Tang Shuhan Yang +9 位作者 Shuxuan Li Xiuli Yue Ting Jin Xinyu Yang Kai Zhang Qianqian Yang Tengfei Liu Shancen Zhao Junyi Gai Yan Li 《Journal of Integrative Plant Biology》 2026年第1期75-95,共21页
Soybean is an important source of oil,protein,and feed.However,its yield is far below that of major cereal crops.The green revolution increased the yield of cereal crops partially through high-density planting of lodg... Soybean is an important source of oil,protein,and feed.However,its yield is far below that of major cereal crops.The green revolution increased the yield of cereal crops partially through high-density planting of lodging-resistant semi-dwarf varieties,but required more nitrogen fertilizers,posing an environmental threat.Genes that can improve nitrogen use efficiency need to be integrated into semi-dwarf varieties to avoid the overuse of fertilizers without the loss of dwarfism.Unlike cereal crops,soybean can assimilate atmospheric nitrogen through symbiotic bacteria.Here,we created new alleles of Gm GID1-2(Glycine max GIBBERELLIN INSENSITIVE DWARF 1-2)using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated nuclease 9(Cas9)editing,which improved soybean architecture,yield,seed oil content,and nitrogen fixation,by regulation of important pathways and known genes related to branching,lipid metabolism,and nodule symbiosis.Gm GID1-2 knockout reduced plant height,and increased stem diameter and strength,number of branches,nodes on the primary stem,pods,and seeds per plant,leading to an increase in seed weight per plant and yield in soybean.The nodule number,nodule weight,nitrogenase activity,and nitrogen content were also improved in Gm GID1-2knockout soybean lines,which is novel compared with the semi-dwarf genes in cereal crops.No loss-of-function allele for Gm GID1-2 was identified in soybean germplasm and the edited Gm GID1-2s are superior to the natural alleles,suggesting the Gm GID1-2 knockout mutants generated in this study are valuable genetic resources to further improve soybean yield and seed oil content in future breeding programs.This study illustrates the pleiotropic functions of the GID1 knockout alleles with positive effects on plant architecture,yield,and nitrogen fixation in soybean,which provides a promising strategy toward sustainable agriculture. 展开更多
关键词 genetic modification natural variation nitrogen fixation plant architecture seed oil content SOYBEAN YIELD
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Minimally invasive four-point scleral refixation for dislocated 4-haptic IOL by horizontal mattress sutures and Hoffman pockets
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作者 Zhao-Liang Zhang Jia-Hui Shen +3 位作者 Jun-Yi Chen Qin-Tuo Pan Xu-Ting Hu Zong-Duan Zhang 《International Journal of Ophthalmology(English edition)》 2026年第3期483-489,共7页
AIM:To evaluate the clinical outcomes of a new minimally invasive technique using horizontal mattress sutures and Hoffman pockets for four-point refixation of dislocated fourhaptic intraocular lenses(IOLs).METHODS:Thi... AIM:To evaluate the clinical outcomes of a new minimally invasive technique using horizontal mattress sutures and Hoffman pockets for four-point refixation of dislocated fourhaptic intraocular lenses(IOLs).METHODS:This retrospective consecutive case series included eyes with dislocated Akreos AO60 IOLs underwent scleral refixation using a horizontal mattress doubleneedle suture technique with intralamellar knot burial via Hoffman pockets.Clinical outcomes assessed included pre-and postoperative best-corrected visual acuity(BCVA),intraocular pressure(IOP),spherical equivalent(SE),suture duration,IOL centration,and perioperative complications.RESULTS:A total of 10 eyes from 10 patients(6 males)were included.The mean age at the time of IOL refixation was 53.10±13.07y(range:28-68y).The mean interval between initial IOL implantation and dislocation was 8.44±3.54y.The mean postoperative follow-up duration was 11.45±10.30mo.Surgical time averaged 15.3±1.77min,with no intraoperative complications.The mean axial length was 27.16±4.35 mm,with high myopia(HM)as the leading comorbidity(4/10 eyes).Postoperative BCVA significantly improved compared to preoperative values(P=0.025).Postoperative SE was significantly improved compared with preoperative(P=0.01).All IOLs remained centered throughout follow-up.CONCLUSION:This minimally invasive four-point scleral fixation technique offers a safe and effective refixation strategy for dislocated four-haptic IOLs.The horizontal mattress suture configuration combined with Hoffman pockets facilitates durable centration,avoids conjunctival dissection,and could be adopted into routine surgical practice. 展开更多
关键词 intraocular lens dislocation four-haptic intraocular lens intraocular lens refixation scleral fixation horizontal mattress suture Hoffman pocket minimally invasive ophthalmic surgery
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Cu doping induced lattice distortion and oxygen vacancy formation in PbBiO_(2)Br:Band structure modulation enhances photocatalytic nitrogen fixation and pollutant degradation performance
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作者 Shude Yuan Yekang Zheng +6 位作者 Yuxin Chu Chuanqi Xia Ruoyu Dong Jiating Xu Botao Teng Ying Wu Yiming He 《Green Energy & Environment》 2026年第1期211-223,共13页
Photocatalytic nitrogen fixation has emerged as a sustainable alternative for ammonia synthesis,playing a crucial role in alleviating energy shortages and environmental pollution.In this study,PbBiO_(2)Br was applied ... Photocatalytic nitrogen fixation has emerged as a sustainable alternative for ammonia synthesis,playing a crucial role in alleviating energy shortages and environmental pollution.In this study,PbBiO_(2)Br was applied to photocatalytic nitrogen fixation for the first time,and its photocatalytic performance was effectively enhanced through Cu doping.The catalyst was synthesized via a simple reduction method,and its morphology,structure,and physicochemical properties were systematically investigated using various characterization techniques and density functional theory calculations.The results revealed that the incorporation of Cu2+partially replaced Pb2+,inducing lattice distortion in PbBiO_(2)Br,promoting the formation of oxygen vacancies,and modifying its electronic band structure.Specifically,Cu doping led to a slight bandgap narrowing,a reduction in work function,and a significant upward shift in the conduction band position.These changes enhanced light absorption,facilitated charge carrier migration and separation,and improved the reduction ability of photogenerated electrons.Moreover,Cu doping promoted N_(2)adsorption and activation.Consequently,the photocatalytic nitrogen fixation performance of Cu-doped PbBiO_(2)Br was significantly enhanced,achieving an optimal nitrogen fixation rate of 293μmol L^(−1)g^(−1)h^(−1),which is 3.6 times higher than that of pristine PbBiO_(2)Br.Additionally,Cu–PbBiO_(2)Br also showed good activity in the photocatalytic degradation of RhB,with a degradation rate 4.6 times higher than that of PbBiO_(2)Br.This work offers new insights into the application of PbBiO_(2)Br in photocatalytic nitrogen fixation and offers valuable guidance for the development of highly efficient nitrogen fixation materials in the future. 展开更多
关键词 PbBiO_(2)Br Cu doping Oxygen vacancy Charge separation Photocatalytic N_(2)fixation
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CO_(2)utilization and fixation in biomass-derived furanics conversion:Thermochemical and electrochemical pathways
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作者 Saeideh Gharouni Fattah Sabah Karimi +5 位作者 Shaoyu Yuan Zheng Li Mohammad Jalal Zohuriaan-Mehr Lu Lin Xianhai Zeng Buxing Han 《Green Energy & Environment》 2026年第1期1-22,共22页
Carbon dioxide(CO_(2))is the main greenhouse gas(GHG)released by human activities.The substitution of fossil resources by biomass as a bio-renewable resource,has significant potential to reduce GHG emissions.The appro... Carbon dioxide(CO_(2))is the main greenhouse gas(GHG)released by human activities.The substitution of fossil resources by biomass as a bio-renewable resource,has significant potential to reduce GHG emissions.The approach to biomass,as the only true full-scale alternative to fossil resources,is progressing rapidly.Converting biomass into furanic compounds,as versatile platform chemicals for synthesizing a wide range of bio-based products is the cornerstone of sustainable technologies.The extensive body of this review combines the biomass valorization to furanic compounds by CO_(2)utilization and furanic compounds conversion by CO_(2)fixation.These processes can be strategically applied through both‘thermochemical’and‘electrochemical’pathways,by utilizing CO_(2)from the atmosphere or industrial emission point and returning it to the natural carbon cycle.In the thermochemical pathway CO_(2)acts as a carbon source(carboxylation and polymerization)or active reaction assistant in the biomass conversion(CO_(2)-assisted conversion),without altering its oxidation state,facilitating the synthesis of valuable products and polymers.Conversely,in the electrochemical pathway,CO_(2)can be used as a carbon source(electrocarboxylation)to give the corresponding carboxylic acid,or it can undergo reduction,yielding methanol,carbon monoxide(CO),formic acid,and analogous compounds,while on the other side,furanic compounds undergo oxidation yielding high-value-added chemicals.Finally,potential future research directions are suggested to promote CO_(2)utilization and fixation in the valorization of biomass-derived furanic compounds,and challenges facing further research are highlighted. 展开更多
关键词 CO_(2)utilization and fixation Biomass valorization Furanic compounds Thermochemical and electrochemical pathways Renewable and sustainable resources
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Bi-Bi_(2)Ti_(2)O_(7) ohmic junction:Dual electron channels driving efficient photocatalytic nitrogen fixation
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作者 Pengkun Li Runjie Wu +5 位作者 Shuai Gao Zeping Qin Mingming Sun Changzheng Wang Wenming Sun Qiang Wang 《Chinese Chemical Letters》 2026年第1期563-569,共7页
Photocatalysis uses solar energy to convert nitrogen and water directly into ammonia,helping reduce dependence on fossil fuels and offering a way to integrate the nitrogen cycle into a clean energy network.Ohmic junct... Photocatalysis uses solar energy to convert nitrogen and water directly into ammonia,helping reduce dependence on fossil fuels and offering a way to integrate the nitrogen cycle into a clean energy network.Ohmic junctions between metals and semiconductors have demonstrated significant advantages in enhancing stability and reducing carrier recombination,but their application in photocatalytic nitrogen fixation is limited due to the difficulty of work function matching and the complexity of fabrication processes.In this study,density functional theory(DFT) calculations were used to confirm the work function matching between Bi and Bi_(2)Ti_(2)O_(7)(BTO),ensuring the formation of an Ohmic junction.A Bi-Bi_(2)Ti_(2)O_(7)(B-BTO) composite was successfully synthesized via a one-step hydrothermal method,using bismuth nitrate and titanium sulfate as precursors.Compared to pure BTO,the B-BTO heterojunction,driven by dual electron injection from both metal Bi and BTO,significantly increased the ammonia synthesis rate to 686.95 μmol g^(-1)h^(-1),making it the most active nitrogen fixation material among similar pyrochlorebased catalysts to date.The differential charge density calculations,photocurrent(i-t) measurements,and photoluminescence(PL) tests further validate the role of Ohmic contacts in enhancing charge transfer and prolonging carrier lifetimes.This research provides valuable insight into the application of Ohmic junctions in photocatalytic nitrogen fixation and contributes to advancements in this field. 展开更多
关键词 PHOTOCATALYTIC N_(2)fixation Ohmic junction Dual electron channels Bi_(2)Ti_(2)O_(7)
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Healthcare professionals’perspectives on disclosure of diagnosis and related issues in childhood cancer:A mixed methods systematic review
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作者 Run Xie Xiaoyan Huang +4 位作者 Yiran Du Ying Gu Qiongfang Kang Hongsheng Wang Daqian Zhu 《International Journal of Nursing Sciences》 2026年第1期96-104,I0006,共10页
Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of... Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of informing the optimization of disclosure processes and meeting the communication needs of affected families.Methods In accordance with the Joanna Briggs Institute(JBI)methodology for mixed methods systematic reviews,the convergent segregated approach was used in this review.Articles were retrieved from 11 databases,including PubMed,Web of Science,CINAHL,CENTRAL,Embase,Ovid/Medline,PsycINFO,PsycArticles,Scopus,ERIC,and China National Knowledge Infrastructure(CNKI).The quality of the selected articles was assessed using the Mixed Method Appraisal Tool(MMAT).The review protocol was registered on PROSPERO(CRD42024542746).Results A total of 21 studies from 10 countries were included.Their methodological quality was generally medium to high,with MMAT scores ranging from 60%to 100%.The synthesis yielded three core themes:1)the spectrum of professional and societal attitudes toward disclosure;2)the dynamic practices of navigating disclosure amid uncertainty,including timing and environment,stakeholders,and content of disclosure;and 3)factors influencing disclosure,including children’s,parental,healthcare professionals’,and socio-cultural factors.Conclusions This review synthesized the perspectives and experiences of healthcare professionals regarding disclosure in childhood cancer,highlighting the complexity and multidimensional nature of this process in clinical practice.Future research should further investigate the experiences and needs of children and their parents,explore cultural variations in disclosure practices,develop context-appropriate assessment tools,and construct multidimensional intervention strategies to enhance the humanistic care and professional effectiveness of the disclosure process. 展开更多
关键词 Communication CANCER DISCLOSURE Healthcare professionals Mixed methods PEDIATRIC Systematic review
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Subtitle Translation Methods of The Good Wife From Functional Equivalence Perspective
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作者 WANG Ya-kun BAO De-wang 《Journal of Literature and Art Studies》 2026年第1期26-30,共5页
The Good Wife is an American TV series that focuses on women’s independence,politics,and law.The drama has been remade in China,Japan,and South Korea.This research aims to use Nida’s Functional Equivalence Theory to... The Good Wife is an American TV series that focuses on women’s independence,politics,and law.The drama has been remade in China,Japan,and South Korea.This research aims to use Nida’s Functional Equivalence Theory to analyze the methods of its English-to-Chinese subtitle translation by considering social,cultural,and historic backgrounds between China and America.After data collection and case analysis,the study found that:(1)Five major translation methods are adopted in the subtitle translation of The Good Wife.They are free translation,variation,literal translation,addition,and omission.Among them,free translation is the most frequently used,while omission is used least.(2)The subtitle translation of films and TV series is limited by time and space restrictions,social-cultural differences,and other factors.When translating,translators should try to use humorous words,euphemism,intonation,and other ways,and combine different methods such as literal translation,free translation,variation,addition,omission,and other methods to seek equivalence both in the meaning and function of subtitles under the guidance of Functional Equivalence Theory. 展开更多
关键词 subtitle translation Functional Equivalence Theory The Good Wife translation methods
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Promoting psychological well-being in AI-enhanced english as a foreign language learning:A mixed-methods study of motivation,language learning anxiety and trust in higher education
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作者 Zhiyong Sun 《Journal of Psychology in Africa》 2026年第1期33-43,共11页
This mixed-methods study investigated how AI-enhanced English as a Foreign Language(EFL)learning environments influence students’psychological well-being through the mediating roles of motivation and language learnin... This mixed-methods study investigated how AI-enhanced English as a Foreign Language(EFL)learning environments influence students’psychological well-being through the mediating roles of motivation and language learning anxiety and the moderating role of trust.Participants were Chinese university students(N=310,62%female,mean age=18.9,SD=0.8),of whom 15 completed interviews to both add to and to clarify the evidence from the surveys.Structural equation modeling results revealed that AI use had significant indirect effects on well-being through increased motivation and reduced language learning anxiety.Trust in AI significantly moderated both paths,amplifying the motivational benefits and anxiety reduction associated with AI use.Thematic analysis supported these results,identifying three experiential themes:(1)motivational empowerment through personalization,(2)anxiety regulation through safe practice and feedback,and(3)trust as the emotional bridge between AI and well-being.The study extends AI psychology applications by empirically linking technology engagement with affective outcomes and underscores the need for human-centered and trust-enhancing design in AI-supported education.From these findings,we conclude that adaptive,transparent,and autonomy-supportive AI systems promote self-determined motivation,emotional safety,and overall psychological health among EFL learners. 展开更多
关键词 Artificial intelligence psychology EFL learning MOTIVATION anxiety trust WELL-BEING mixed methods self-determination theory
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Observation on the therapeutic effect of a modified Devine procedure with subcutaneous sliding fixation method for concealed penis
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作者 Mohammed Abdulkarem Al-Qaisi Hai-Fu Tian +8 位作者 Jia-Jin Feng Ke-Ming Chen Jin Zhang Yun-Shang Tuo Xue-Hao Wang Bin-Cheng Huang Muhammad Arslan Ul Hassan Rui He Guang-Yong Li 《Asian Journal of Andrology》 2025年第4期470-474,共5页
To evaluate the therapeutic effect of a modified Devine procedure with a subcutaneous sliding fixation method for the treatment of congenital concealed penis,we retrospectively selected 45 patients with congenital con... To evaluate the therapeutic effect of a modified Devine procedure with a subcutaneous sliding fixation method for the treatment of congenital concealed penis,we retrospectively selected 45 patients with congenital concealed penises who were admitted to General Hospital of Ningxia Medical University(Yinchuan,China)between September 2020 and November 2023.In all cases,the penis was observed to be short,and retracting the skin at the base revealed a normal penile body,which immediately returned to its original position upon release.All patients underwent the modified Devine procedure with subcutaneous sliding fixation and completed a 12-week postoperative follow-up.A statistically significant increase in penile length was observed postoperatively,with the median length increasing from 4.0(interquartile range[IQR]:3.5–4.8;95%confidence interval[CI]:3.9–4.4)cm to 8.0(IQR:7.8–8.0;95%CI:7.7–7.9)cm,with P<0.001.The parents were satisfied with the outcomes,including increased penile length,improved hygiene,and enhanced esthetics.Except for mild foreskin edema in all cases,no complications(such as infections,skin necrosis,or penile retraction)were observed.The edema was resolved within 4 weeks after the operation.This study demonstrates that the modified Devine procedure utilizing the subcutaneous sliding fixation method yields excellent outcomes with minimal postoperative complications,reduced penile retraction,and high satisfaction rates among patients and their families. 展开更多
关键词 congenital concealed penis fixation method modified Devine surgery
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Optimized nitrogen application methods to improve nitrogen use efficiency and nodule nitrogen fixation in a maize-soybean relay intercropping system 被引量:21
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作者 YONG Tai-wen CHEN Ping +5 位作者 DONG Qian DU Qing YANG Feng WANG Xiao-chun LIU Wei-guo YANG Wen-yu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第3期664-676,共13页
In China, the abuse of chemical nitrogen (N) fertilizer results in decreasing N use efficiency (NUE), wasting resources and causing serious environmental problems. Cereal-legume intercropping is widely used to enh... In China, the abuse of chemical nitrogen (N) fertilizer results in decreasing N use efficiency (NUE), wasting resources and causing serious environmental problems. Cereal-legume intercropping is widely used to enhance crop yield and improve resource use efficiency, especially in Southwest China. To optimize N utilization and increase grain yield, we conducted a two-year field experiment with single-factor randomized block designs of a maize-soybean intercropping system (IMS). Three N rates, NN (no nitrogen application), LN (lower N application: 270 kg N ha-1), and CN (conventional N application: 330 kg N ha-1), and three topdressing distances of LN (LND), e.g., 15 cm (LND1), 30 cm (LND2) and 45 cm (LND3) from maize rows were evaluated. At the beginning seed stage (R5), the leghemoglobin content and nitrogenase activity of LND3 were 1.86 mg plant-1 and 0.14 mL h-1 plant-1, and those of LND1 and LND2 were increased by 31.4 and 24.5%, 6.4 and 32.9% compared with LND3, respectively. The ureide content and N accumulation of soybean organs in LND1 and LND2 were higher than those of LND3. The N uptake, NUE and N agronomy efficiency (NAE) of IMS under CN were 308.3 kg ha-1, 28.5%, and 5.7 kg grain kg-1 N, respectively; however, those of LN were significantly increased by 12.4, 72.5, and 51.6% compared with CN, respectively. The total yield in LND1 and LND2 was increased by 12.3 and 8.3% compared with CN, respectively. Those results suggested that LN with distances of 15-30 cm from the topdressing strip to the maize row was optimal in maize-soybean intercropping. Lower N input with an optimized fertilization location for IMS increased N fixation and N use efficiency without decreasing grain yield. 展开更多
关键词 relay intercropping lower nitrogen nitrogen use efficiency nitrogen fixation nitrogen uptake
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Tunnel ahead prospecting methods and intelligent interpretation of adverse geology:A review
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作者 Shucai Li Bin Liu +4 位作者 Lei Chen Huaifeng Sun Lichao Nie Zhengyu Liu Yuxiao Ren 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期1-19,共19页
Geological prospecting and the identification of adverse geological features are essential in tunnel construction,providing critical information to ensure safety and guide engineering decisions.As tunnel projects exte... Geological prospecting and the identification of adverse geological features are essential in tunnel construction,providing critical information to ensure safety and guide engineering decisions.As tunnel projects extend into deeper and more mountainous terrains,engineers face increasingly complex geological conditions,including high water pressure,intense geo-stress,elevated geothermal gradients,and active fault zones.These conditions pose substantial risks such as high-pressure water inrush,largescale collapses,and tunnel boring machine(TBM)blockages.Addressing these challenges requires advanced detection technologies capable of long-distance,high-precision,and intelligent assessments of adverse geology.This paper presents a comprehensive review of recent advancements in tunnel geological ahead prospecting methods.It summarizes the fundamental principles,technical maturity,key challenges,development trends,and real-world applications of various detection techniques.Airborne and semi-airborne geophysical methods enable large-scale reconnaissance for initial surveys in complex terrain.Tunnel-and borehole-based approaches offer high-resolution detection during excavation,including seismic ahead prospecting(SAP),TBM rock-breaking source seismic methods,fulltime-domain tunnel induced polarization(TIP),borehole electrical resistivity,and ground penetrating radar(GPR).To address scenarios involving multiple,coexisting adverse geologies,intelligent inversion and geological identification methods have been developed based on multi-source data fusion and artificial intelligence(AI)techniques.Overall,these advances significantly improve detection range,resolution,and geological characterization capabilities.The methods demonstrate strong adaptability to complex environments and provide reliable subsurface information,supporting safer and more efficient tunnel construction. 展开更多
关键词 Tunnel geological ahead prospecting Complex geological and environmental conditions Airborne geophysical methods Tunnel geophysical detection Borehole geophysical prospecting Intelligent geological interpretation
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Three-dimensional finite element analysis with different internal fixation methods through the anterior approach 被引量:3
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作者 Xian-Jin Xie Sheng-Lu Cao +2 位作者 Kai Tong Zi-Yi Zhong Gang Wang 《World Journal of Clinical Cases》 SCIE 2021年第8期1814-1826,共13页
BACKGROUND With the modernization of society and transportation in the last decades in China,the incidence of high-energy trauma increased sharply in China,including that of acetabular fractures.AIM To establish diffe... BACKGROUND With the modernization of society and transportation in the last decades in China,the incidence of high-energy trauma increased sharply in China,including that of acetabular fractures.AIM To establish different finite element models for acetabular posterior column fractures involving the quadrilateral area of the acetabulum.METHODS The three-dimensional models of the normal and fractured pelvis and the five internal fixations were established using the computed tomography data of the pelvis of a living volunteer.After the vertebral body model was inserted in the way of origin matching and all cancellous bones were copied using the duplicated cancellous bone model as the subtractive entity,the Boolean operation was performed on the pelvis model to obtain the model of the complete pelvis cortical and cancellous bones.RESULTS In the standing position,the maximum stress was 46.21 MPa.In the sitting position,the sacrum bore the simulated gravity load at the upper end.When comparing the five fixations,there were no significant differences in the stress mean values among groups(sitting:P=0.9794;standing:P=0.9741).In terms of displacement,the average displacement of the internal iliac plate group was smaller than that of the spring plate group(P=0.002),and no differences were observed between the other pairs of groups(all P>0.05).In the standing position,there were no significant differences in the mean value of displacement among the groups(P=0.2985).It can be seen from the stress nephogram of the internal fixations in different positions that the stress of the internal fixation was mainly concentrated in the fracture segment.CONCLUSION There were no significant differences among the fixations for acetabular posterior column fractures involving the quadrilateral area of the acetabulum. 展开更多
关键词 ACETABULUM Hip fractures ANALYSIS Finite element Fracture fixation Orthopedic fixation devices
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Fixation methods for electron microscopy of human and other liver 被引量:1
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作者 Eddie Wisse Filip Braet +8 位作者 Hans Duimel Celien Vreuls Ger Koek Steven WM Olde Damink Maartje AJ van den Broek Bart De Geest Cees HC Dejong Chise Tateno Peter Frederik 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第23期2851-2866,共16页
For an electron microscopic study of the liver,expertise and complicated,time-consuming processing of hepatic tissues and cells is needed.The interpretation of electron microscopy(EM) images requires knowledge of the ... For an electron microscopic study of the liver,expertise and complicated,time-consuming processing of hepatic tissues and cells is needed.The interpretation of electron microscopy(EM) images requires knowledge of the liver fine structure and experience with the numerous artifacts in fixation,embedding,sectioning,contrast staining and microscopic imaging.Hence,the aim of this paper is to present a detailed summary of different methods for the preparation of hepatic cells and tissue,for the purpose of preserving long-standing expertise and to encourage new investigators and clinicians to include EM studies of liver cells and tissue in their projects. 展开更多
关键词 LIVER Tissue fixation PERFUSION Electron microscopy BIOPSY
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Soil NH_4^+ Fixation and Fertilizer N Recovery as Affected by Soil Moisture and Fertilizer Application Methods 被引量:6
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作者 TONGYan-Ani O.EMTERYD +1 位作者 H.GRIP LUDian-Qing 《Pedosphere》 SCIE CAS CSCD 2004年第2期247-252,共6页
Ammonium fixation and the effects of soil moisture and application methods on fertilizer N recovery were investigated in two soils of Shaanxi Province,China,a Luvisol and an Entisol,through two experiments performed i... Ammonium fixation and the effects of soil moisture and application methods on fertilizer N recovery were investigated in two soils of Shaanxi Province,China,a Luvisol and an Entisol,through two experiments performed in the laboratory and in a glass shelter,respectively,by using ammonium bicarbonate (NH4HCO3). The laboratory closed incubation box experiment was conducted using the Luvisol to study NH4+ fixation rate at soil moisture levels of 10.1%,22.7% and 35.3% water filled pore space (WFPS). The fixed NH4+-N increased dramatically to 51% and 66%,67% and 74%,and 82% and 85% 1,2 and 36 h after fertilizer incorporation at moisture levels of 10.1% and 22.7% WFPS and 35.3%WFPS,respectively. The rapid NH4+ fixation rates at all moisture levels could help prevent NH4+ losses from ammonia volatilization. In the glass shelter pot experiment,N fertilizer was applied by either banding (in a concentrated strip)or incorporating (thoroughly mixing) with the Entisol and the Luvisol. An average of 74.2% of the added N fertilizer was recovered 26 days after application to the Luvisol,while only 61.4% could be recovered from the Entisol,due to higher NH4+ fixation capacity of the Luvisol. The amount of fixed NH4+ decreased with increasing WFPS. The amount of fixed NH4+ in the incorporated fertilizer treatment was,on average,10% higher than that in the banded treatment.Higher NH4+ fixation rates could prevent N loss and thus increase N recovery. The results from the Luvisol showed lower nitrogen recovery as soil moisture level increased,which could be explained by the fact that most of the fixed NH4+ was still not released when the soil moisture level was low. When the fertilizer was incorporated into the soil,the recovery of N increased,compared with the banded treatment,by an average of 26.2% in the Luvisol and 11.2% in the Entisol,which implied that when farmers applied fertilizer,it would be best to mix it well with the soil. 展开更多
关键词 fertilizer application N recovery NH4+ fixation soil moisture
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The Effects of Different Fixation Methods on Quality of Lycium ruthenicum Murr Bud-tea 被引量:1
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作者 Xiaoying LI Heying AI +5 位作者 Xiyan ZHANG Yamei YAN Lanying LIU Jia MI Lu LU Jun HE 《Agricultural Biotechnology》 CAS 2018年第6期176-177,180,共3页
The effects of three fixation methods( steaming,blanching and microwave fixation) on chemical composition and sensory quality of Lycium ruthenicum bud-tea were investigated.The results showed the fixation technique( t... The effects of three fixation methods( steaming,blanching and microwave fixation) on chemical composition and sensory quality of Lycium ruthenicum bud-tea were investigated.The results showed the fixation technique( the leaf weight 3 g/cm^2,the time 1.5 min,and the temperature 100 ℃) was the best,which was beneficial to the conservation of free amino acid and soluble sugar in L.ruthenicum bud-tea.The loss of chlorophyll was limited,and the score of sensory quality review was higher. 展开更多
关键词 LYCIUM ruthenicum bud-tea fixation QUALITY
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Comparative study of various internal fixation methods for treating patellar fractures by three-dimensional photoelasticity 被引量:2
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作者 许硕贵 苏佳灿 +4 位作者 张春才 曾伟明 顾绍德 张林春 方如华 《Journal of Medical Colleges of PLA(China)》 CAS 2003年第6期384-387,共4页
Objective: To compare the biomechanical basis of 3 different internal fixation methods: nitinol patellar concentrator (NT-PC), tension band and wire circle in treating patellar fractures. Methods: The epoxy resin thre... Objective: To compare the biomechanical basis of 3 different internal fixation methods: nitinol patellar concentrator (NT-PC), tension band and wire circle in treating patellar fractures. Methods: The epoxy resin three dimensional photoelasticity patellar models were made by precise moulding, and were fixated by nitinol patellar concentrator (NT-PC), tension band and wire circle respectively. The patellar models with frozen stress stripes were put into the polarized light field and the stress distributions were compared. As for the model fixated by NT-PC, by dividing layer, photographing and tracing, we used the iterative method to calculate the stress value of every internal node of the epoxy resin patellar model, and the character of stress was analyzed. Results: An overall stress field was yielded when the patellar model was fixated by NT-PC, and the stripes were more than that of tension band model and wire circle model, which have only few stress stripes in the fixated layers. Further analysis indicated that there were continuous fixated stresses in the facies articularis and distal pole of patella, and the character of stresses produced by NT-PC were mainly in longitudinal direction, then in transverse direction. The shearing stresses were small. Conclusion: The initiative and continuous memorial stress of NT-PC and its overall stress distribution character are the essence of NT-PC distinguished with tension band and wire circle in treating patellar fractures. The stress character produced by NT-PC is good for the stability of fracture site and prompts fracture healing. 展开更多
关键词 internal fixation patellar fracture PHOTOELASTICITY STRESS nitinol patellar concentrator
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