bluuebunny/crossref_metadata_2025 huggingface dataset:
Pseudo‐Elasticity and Variable Electro‐Conductivity Mediated by Size‐Dependent Deformation Twinning in Molybdenum Nanocrystals
Authors: Peng Huayu , Hou Yuxuan , Meng Weiwei , Zheng He , Zhao Ligong , Zhang Ying , Li Kaixuan , Zhao Peili , Liu Ting , Jia Shuangfeng , Wang Jianbo
Published: February 2023

Deformation twinning merits attention because of its intrinsic importance as a mode of energy dissipation in solids. Herein, through the atomistic electron microscopy observations, the size‐dependent twinning mechanisms in refractory body‐centered cubic molybdenum nanocrystals (NCs) under tensile loading are shown. Two distinct twinning mechanisms involving the nucleation of coherent and inclined twin boundaries (TBs) are uncovered in NCs with smaller (diameter < ≈5 nm) and larger (diameter > ≈5 nm) diameters, respectively. Interestingly, the ultrahigh pseudo‐elastic strain of ≈41% in sub‐5 nm‐sized crystals is achieved through the reversible twinning mechanism. A typical TB cross‐transition mechanism is found to accommodate the NC re‐orientation during the pseudo‐elastic deformation. More importantly, the effects of different types of TBs on the electrical conductivity based on the repeatable experimental measurements and first‐principles calculations are quantified. These size‐dependent mechanical and electrical properties may prove essential in advancing the design of next‐generation flexible nanoelectronics.
Engineered Organic Nanorockets with Light‐Driven Ultrafast Transportability for Antitumor Therapy
Authors: Feng Ao , Cheng Xie , Huang Xing , Liu Yang , He Zhaoxia , Zhao Juan , Duan Huiyan , Shi Zhiqing , Guo Jintang , Wang Shuai , Yan Xibo
Published: February 2023

Nanomedicines confront various complicated physiological barriers limiting the accumulation and deep penetration in the tumor microenvironment, which seriously restricts the efficacy of antitumor therapy. Self‐propelled nanocarriers assembled with kinetic engines can translate external energy into orientated motion for tumor penetration. However, achieving a stable ultrafast permeability at the tumor site remains challenging. Here, sub‐200 nm photoactivated completely organic nanorockets (NRs), with asymmetric geometry conveniently assembled from photothermal semiconducting polymer payload and thermo‐driven macromolecular propulsion through a straightforward nanoprecipitation process, are presented. The artificial NRs can be remotely manipulated by 808 nm near‐infrared light to trigger the photothermal conversion and Curtius rearrangement reaction within the particles for robustly pushing nitrogen out into the solution. Such a two‐stage light‐to‐heat‐to‐chemical energy transition effectively powers the NRs for an ultrafast (≈300 µm s−1) and chemical medium‐independent self‐propulsion in the liquid media. That endows the NRs with high permeability against physiological barriers in the tumor microenvironment to directionally deliver therapeutic agents to target lesions for elevating tumor accumulation, deep penetration, and cellular uptake, resulting in a significant enhancement of antitumor efficacy. This work will inspire the design of advanced kinetic systems for powering intelligent nanomachines in biomedical applications.
Luminescent Carbon Nanodots Doped with Gadolinium (III): Purification Criteria, Chemical and Biological Characterization of a New Dual Fluorescence/MR Imaging Agent
Authors: Cardo Lucia , Martínez‐Parra Lydia , Cesco Michele , Echeverría‐Beistegui Begoña M. , Martínez‐Moro Marta , Herrero‐Álvarez Natalia , Cabrerizo Marta‐Beraza , Carregal‐Romero Susana , Ramos‐Cabrer Pedro , Ruiz‐Cabello Jesús , Prato Maurizio
Published: February 2023

Carbon Dots (CDs) are luminescent quasi‐spherical nanoparticles, possessing water solubility, high biocompatibility, and tunable chemical and physical properties for a wide range of applications, including nanomedicine and theranostics. The evaluation of new purification criteria, useful to achieve more reliable CDs, free from the interference of artifacts, is currently an object of debate in the field. Here, new CDs doped with gadolinium (Gd (III)), named Gd@CNDs, are presented as multifunctional probes for Magnetic Resonance Imaging (MRI). This new system is a case of study, to evaluate and/or combine different purification strategies, as a crucial approach to generate CDs with a better performance. Indeed, these new amorphous Gd@CNDs display good homogeneity, and they are free from emissive side products. Gd@CNDs (7–10 nm) contain 7% of Gd (III) w/w, display suitable and stable longitudinal relaxivity (r1) and with emissive behavior, therefore potentially useful for both MR and fluorescence imaging. They show good biocompatibility in both cellular and in vivo studies, cell permeability, and the ability to generate contrast in cellular pellets. Finally, MRI recording T1‐weighted images on mice after intravenous injection of Gd@CNDs, show signal enhancement in the liver, spleen, and kidney 30 min postinjection.
Physiologically‐Based Kinetic Modeling of Intravenously Administered Gold (Au) Nanoparticles
Authors: Minnema Jordi , Vandebriel Rob J , Boer Karin , Klerx Walther , De Jong Wim H. , Delmaar Christiaan J. E.
Published: February 2023

Physiologically‐based kinetic (PBK) modeling is a valuable tool to understand the kinetics of nanoparticles (NPs) in vivo. However, estimating PBK parameters remains challenging and commonly requires animal studies. To develop predictive models to estimate PBK parameter values based on NP characteristics, a database containing PBK parameter values and corresponding NP characteristics is needed. As a first step toward this objective, this study estimates PBK parameters for gold NPs (AuNPs) and provides a comparison of two different NPs. Two animal experiments are conducted in which varying doses of AuNPs attached with polyethylene glycol (PEG) are administered intravenously to rats. The resulting Au concentrations are used to estimate PBK model parameters. The parameters are compared with PBK parameters previously estimated for poly(alkyl cyanoacrylate) NPs loaded with cabazitaxel and for LipImage 815. This study shows that a small initial database of PBK parameters collected for three NPs is already sufficient to formulate new hypotheses on NP characteristics that may be predictive of PBK parameter values. Further research should focus on developing a larger database and on developing quantitative models to predict PBK parameter values.
Significantly Stabilizing Hydrogen Evolution Reaction Induced by Nb‐Doping Pt/Co(OH)2 Nanosheets
Authors: Tian Yakun , Wen Ming , Huang Aijian , Wu Qingsheng , Wang Zhiguo , Zhu Quanjing , Zhou Tao , Fu Yongqing
Published: February 2023

High stability and efficiency of electrocatalysts are crucial for hydrogen evolution reaction (HER) toward water splitting in an alkaline media. Herein, a novel nano‐Pt/Nb‐doped Co(OH)2 (Pt/NbCo(OH)2) nanosheet is designed and synthesized using water‐bath treatment and solvothermal reduction approaches. With nano‐Pt uniformly anchored onto NbCo(OH)2 nanosheet, the synthesized Pt/NbCo(OH)2 shows outstanding electrocatalytic performances for alkaline HER, achieving a high stability for at least 33 h, a high mass activity of 0.65 mA µg−1 Pt, and a good catalytic activity with a low overpotential of 112 mV at 10 mA cm−2. Both experimental and theoretical results prove that Nb‐doping significantly optimizes the hydrogen adsorption free energy to accelerate the Heyrovsky step for HER, and boosts the adsorption of H2O, which further enhances the water activation. This study provides a new design methodology for the Nb‐doped electrocatalysts in an alkaline HER field by facile and green way.
The Precision Defect Engineering with Nonmetallic Element Refilling Strategy in g‐C3N4 for Enhanced Photocatalytic Hydrogen Production
Authors: Liu Yujie , Tayyab Muhammad , Pei Wenkai , Zhou Liang , Lei Juying , Wang Lingzhi , Liu Yongdi , Zhang Jinlong
Published: February 2023

Traditional defect engineering and doping strategies are considered effective means for improving H2 evolution, but the uncontrollability of the modification process does not always lead to efficient activity. A defect‐induced heteroatom refilling strategy is used here to synthesize heteroatoms introduced carbon nitride by precisely controlling the “introduction” sites on efficient N1 sites. Density functional theory calculations show that the refilling of B, P, and S sites have stronger H2O adsorption and dissociation capacity than traditional doping, which makes it an optimal H2 production path. The large internal electric field strength of heteroatom‐refilled catalysts leads to fast electron transfer and the hydrogen production of the best sample is up to 20.9 mmol g−1 h−1. This work provides a reliable and clear insight into controlled defect engineering of photocatalysts and a universal modification strategy for typical heteroatom and co‐catalyst systems for H2 production.
Initiating Fluorine Chemistry in Polycyclic Aromatic Hydrocarbon‐Derived Carbon for New Cluster‐Mode Na Storage with Superhigh Capacity
Authors: Shao Yuan , Cui Yahui , Wang Changda , Yang Qi , Hong Song , Tang Yongchao , Zhang Yong , Guo Xin , Zhang Lipeng , Song Li , Qiu Jieshan
Published: February 2023

Carbon materials are widely accepted as promising candidates for sodium‐ion batteries (SIBs) anodes due to their chemical stability and conductivity, while the capacity is still unsatisfactory. Here, this work reports the superhigh capacity Na storage through initiating fluorine chemistry (CF bonds) in carbon synthesized by the dehydrogenation and fluorination of polycyclic aromatic hydrocarbon such as pitch. Experimental and theoretical investigations uncover that CF bonds exist at the form of dangling bonds (CFx), which generates the coexistence of graphitic and defective nanodomains. It delivers a superhigh capacity of 450 mAh g−1, far surpassing most of current SIBs carbon anodes. Theoretical calculation attributes this performance to a new Na storage mechanism that Na can be accommodated in the form of cluster rather than a single ion at each host site with F‐doping. This work highlights the significance of carbon material chemistry in establishing the novel ion storage manner in SIBs and other batteries.
High‐Energy Aqueous Magnesium Ion Batteries with Capacity‐Compensation Evolved from Dynamic Copper Ion Redox
Authors: Zhang Shuxin , Wang Yaowei , Sun Yukun , Wang Yaru , Yang Yang , Zhang Peng , Lv Xuecheng , Wang Jiulin , Zhu Hong , NuLi Yanna
Published: February 2023

The low specific capacity and low voltage plateau are significant challenges in the advancement of practical magnesium ion batteries (MIBs). Here, a superior aqueous electrolyte combining with a copper foam interlayer between anode and separator is proposed to address these drawbacks. Notably, with the dynamic redox of copper ions, the weakened solvation of Mg2+ cations in the electrolyte and the enhanced electronic conductivity of anode, which may offer effective capacity‐compensation to the 3,4,9,10‐perylenetetracarboxylic diimide (PTCDI)‐Mg conversion reactions during the long‐term cycles. As a result, the unique MIBs using expanded graphite cathode coupled with PTCDI anode demonstrate exceptional performance with an ultra‐high capacity (205 mAh g−1, 243 Wh kg−1 at 5 A g−1) as well as excellent cycling stability after 600 cycles and rate capability (138 mAh g−1, 81 Wh kg−1 at 10 A g−1).
Recent Advances in Mechanical Vibration Energy Harvesters Based on Triboelectric Nanogenerators
Authors: Du Taili , Dong Fangyang , Xi Ziyue , Zhu Meixian , Zou Yongjiu , Sun Peiting , Xu Minyi
Published: February 2023

With the development of autonomous/smart technologies and the Internet of Things (IoT), tremendous wireless sensor nodes (WSNs) are of great importance to realize intelligent mechanical engineering, which is significant in the industrial and social fields. However, current power supply methods, cable and battery for instance, face challenges such as layout difficulties, high cost, short life, and environmental pollution. Meanwhile, vibration is ubiquitous in machinery, vehicles, structures, etc., but has been regarded as an unwanted by‐product and wasted in most cases. Therefore, it is crucial to harvest mechanical vibration energy to achieve in situ power supply for these WSNs. As a recent energy conversion technology, triboelectric nanogenerator (TENG) is particularly good at harvesting such broadband, weak, and irregular mechanical energy, which provides a feasible scheme for the power supply of WSNs. In this review, recent achievements of mechanical vibration energy harvesting (VEH) related to mechanical engineering based on TENG are systematically reviewed from the perspective of contact–separation (C‐S) and freestanding modes. Finally, existing challenges and forthcoming development orientation of the VEH based on TENG are discussed in depth, which will be conducive to the future development of intelligent mechanical engineering in the era of IoT.
The Internal Structure of the Velvet Worm Projectile Slime: A Small‐Angle Scattering Study
Authors: Baer Alexander , Hoffmann Ingo , Mahmoudi Najet , Poulhazan Alexandre , Harrington Matthew J. , Mayer Georg , Schmidt Stephan , Schneck Emanuel
Published: February 2023

For prey capture and defense, velvet worms eject an adhesive slime which has been established as a model system for recyclable complex liquids. Triggered by mechanical agitation, the liquid bio‐adhesive rapidly transitions into solid fibers. In order to understand this mechanoresponsive behavior, here, the nanostructural organization of slime components are studied using small‐angle scattering with neutrons and X‐rays. The scattering intensities are successfully described with a three‐component model accounting for proteins of two dominant molecular weight fractions and nanoscale globules. In contrast to the previous assumption that high molecular weight proteins—the presumed building blocks of the fiber core—are contained in the nanoglobules, it is found that the majority of slime proteins exist freely in solution. Only less than 10% of the slime proteins are contained in the nanoglobules, necessitating a reassessment of their function in fiber formation. Comparing scattering data of slime re‐hydrated with light and heavy water reveals that the majority of lipids in slime are contained in the nanoglobules with homogeneous distribution. Vibrating mechanical impact under exclusion of air neither leads to formation of fibers nor alters the bulk structure of slime significantly, suggesting that interfacial phenomena and directional shearing are required for fiber formation.
Size‐Controlled Synthesis of Luminescent Few‐Atom Silver Clusters via Electron Transfer in Isostructural Redox‐Active Porous Ionic Crystals
Authors: Haraguchi Naoya , Ogiwara Naoki , Kumabe Yoshitaka , Kikkawa Soichi , Yamazoe Seiji , Tachikawa Takashi , Uchida Sayaka
Published: February 2023

Ag clusters with a controlled number of atoms have received significant interest because they show size‐dependent catalytic, optical, electronic, or magnetic properties. However, the synthesis of size‐controlled, ligand‐free, and air‐stable Ag clusters with high yields has not been well‐established. Herein, it is shown that isostructural porous ionic crystals (PICs) with redox‐active polyoxometalates (POMs) can be used to synthesize Ag clusters via electron transfer from POMs to Ag+. Ag clusters with average numbers of three, four, or six atoms emitting blue, green, or red colors, respectively, are formed and stabilized in the PICs under ambient conditions without any protecting ligands. The cluster size solely correlates with the degree of electron transfer, which is controlled by the reduction time and types of ions or elements of the PICs. Thus, advantages have been taken of POMs as electron sources and PICs as scaffolds to demonstrate a convenient method to obtain few‐atom Ag clusters.
Electric Eel Biomimetics for Energy Storage and Conversion
Authors: Xiao Xiangting , Mei Yu , Deng Wentao , Zou Guoqiang , Hou Hongshuai , Ji Xiaobo
Published: February 2023

The electric eel is known as the most powerful creature to generate electricity with a discharge voltage up to 860 V and peak current up to 1 A. These surprising properties are the results of billions of years of evolution on the electrical biological structure and bulk, and now have triggered great research interest in electric eel biomimetics for designing innovated configurations and components of energy storage and conversion devices. In this review, first, the bioelectrical behavior of electric eels is surveyed, followed by the physiological structure to reveal the discharge characteristics and principles of electric organs and electrocytes. Additionally, underlying electrochemical mechanisms and models for calculating the potential and current of electrocytes are presented. Central to this review is the recent progress of electric‐eel‐inspired innovations and applications for energy storage and conversion, particularly including novel power sources, triboelectric nanogenerators, and nanochannel ion‐selective membranes for salinity gradient energy harvesting. Finally, insights on the challenges at the moment and the perspectives on the future research prospects are critically compiled. It is suggested that energy‐related electric eel biomimetics will greatly boost the development of next‐generation high performance, green, and functional electronics.
Design Strategies toward High‐Performance Zn Metal Anode
Authors: Nie Wei , Cheng Hongwei , Sun Qiangchao , Liang Shuquan , Lu Xionggang , Lu Bingan , Zhou Jiang
Published: February 2023

Rechargeable aqueous Zn‐ion batteries (AZIBs) are one of the most promising alternatives for traditional energy‐storage devices because of their low cost, abundant resources, environmental friendliness, and inherent safety. However, several detrimental issues with Zn metal anodes including Zn dendrite formation, hydrogen evolution, corrosion and passivation, should be considered when designing advanced AZIBs. Moreover, these thorny issues are not independent but mutually reinforcing, covering many technical and processing parameters. Therefore, it is necessary to comprehensively summarize the issues facing Zn anodes and the corresponding strategies to develop roadmaps for the development of high‐performance Zn anodes. Herein, the failure mechanisms of Zn anodes and their corresponding impacts are outlined. Recent progress on improving the stability of Zn anode is summarized, including structurally designed Zn anodes, Zn alloy anodes, surface modification, electrolyte optimization, and separator design. Finally, this review provides brilliant and insightful perspectives for stable Zn metal anodes and promotes the large‐scale application of AZIBs in power grid systems.
Insights into the Coating Integrity and its Effect on the Electrochemical Performance of Core–Shell Structure SiOx@C Composite Anodes
Authors: Xiao Zhexi , Lin Xianqing , Zhang Chenxi , Shen Jiaqi , Zhang Ruirui , He Ziying , Lin Zhenkang , Jiang Hairong , Wei Fei
Published: February 2023

Silicon‐based anodes have been considered as ideal candidates for next‐generation Li‐ion batteries. However, the rapid cyclability decay due to significant volume expansion limits its commercialization. Besides, the instable interface further aggravates the degradation. Carbon coating is one effective way to improve the electrochemical performance.The coating integrity may be a critical index for core–shell structure electrode materials. Herein, the coating integrity of SiOx@C composite is tested by a developed selective alkali dissolution, further quantitatively depicted by a proposed index of alkali solubility α. The effect of coating integrity on electrochemical performance reveals that SiOx dissolution loss has a significant impact on the overall electrode structure stability and interface property. Because of the side reaction between uncoated active SiOx and electrolyte, the quadratic decrease of initial coulombic efficiency and increase of solid electrolyte interphase thickness with the rise of alkali solubility are closely related to the generated F content induced by active material loss, further supported by the obvious linear rise of Li2SiF6 fraction, leads to the linear increase of interface impedance and volume expansion rate, which may take primarily responsibility for the performance decay. This work propels the fundamental understanding on the interface failure mechnism and inspires rational high‐performance electrode material design.
Green, HF‐Free Synthesis of MXene Quantum Dots and their Photocatalytic Activity for Hydrogen Evolution
Authors: Ramírez Rubén , Melillo Arianna , Osella Silvio , Asiri Abdullah M. , Garcia Hermenegildo , Primo Ana
Published: February 2023

A general methodology to prepare MXene quantum dots (MxQDs) with yields over 20% by liquid‐phase laser ablation of the MAX phase is reported. Mechanical and thermal shock by 532 nm laser pulses (7 ns fwhp, 50 mJ × pulse−1, 1 Hz pulse frequency) produces MAX etching and exfoliation to form MXene QDs, avoiding the use of HF. The process can be followed by absorption and emission spectroscopy and by dynamic laser scattering and it appears to be general, being applied to Ti3AlC2, Ti2AlC, Nb2AlC, and V2AlC MAX phases. Density functional theory calculations indicate that, depending on the surface terminal groups, the diminution of the MXene size to the nanometric scale makes it possible to control the band gap of the MXene. The photocatalytic activity of these MXene QDs for hydrogen evolution has been observed, reaching an H2 production for the most efficient Ti3C2 QDs as high as 2.02 mmol × g−1 × h−1.
Postnatal genetic and neurodevelopmental assessment in infants born at term with severely low birth weight of non‐placental origin
Authors: Paz y Miño M. F. , Pauta M. , Meler E. , Matas I. , Mazarico E. , Camacho A. , Segura M. , Figueras F. , Borrell A.
Published: February 2023

Objective

To determine the frequency of genetic syndromes and childhood neurodevelopmental impairment in non‐malformed infants born at term with severely low birth weight and no evidence of placental insufficiency.

Methods

This case series was constructed from the data of infants delivered at term between 2013 and 2018 with severely low birth weight, defined as birth weight more than 2.5 SD below the mean, with normal maternal and fetal Doppler (umbilical artery, fetal middle cerebral artery, cerebroplacental ratio and uterine artery) and no maternal hypertensive disorder during pregnancy or fetal structural anomaly on prenatal ultrasound examination. Clinical exome sequencing and copy number variation (CNV) analysis were performed using DNA extracted from the children's saliva. Cognitive and psychomotor development was evaluated using the Bayley Scales of Infant and Toddler Development, 3rd edition or the Wechsler Intelligence Scale for Children, 5th edition tests, according to the child's age at testing.

Results

Among the 36 405 infants born within the study period, 274 (0.75%) had a birth weight below –2.5 SD, of whom 98 met the inclusion criteria. Among the 63 families contacted, seven (11%) reported a postnatal diagnosis of a genetic syndrome and a further 18 consented to participate in the study. Median gestational age at delivery was 38.0 (interquartile range (IQR), 37.3–38.5) weeks and median birth weight was 2020 (IQR, 1908–2248) g. All 18 children showed a normal result on clinical exome sequencing and CNV analysis, but six (33%) obtained a low score on neurodevelopmental testing.

Conclusion

Non‐malformed severely small term infants with no clinical or Doppler signs of placental insufficiency present a high rate of genetic syndromes and neurodevelopmental impairment during childhood. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Introduction
Authors: Mari Luca , Wilson Mark , Maul Andrew
Published: February 2023

This chapter aims to justify the importance of the subject of the book and to frame it in a broad structural perspective that leads to a transdisciplinary understanding of measurement of physical and of psychosocial properties, exemplified by the measurement of temperature and of reading comprehension ability respectively. As a first sketch of the feasibility of this integrated framework, a typical method of psychosocial measurement is applied to a case of physical measurement.
Future Challenges for Waterway Hydraulic Structures
Authors: Kunz Claus
Published: February 2023

Looking into the future, (massive) hydraulic structures face a not inconsiderable number of challenges that need to be overcome.
Meshed Remote Operation as the Default Mode: From Technical Challenge to Society Opportunnities
Authors: Peil Anges , Coopman Michiel
Published: February 2023

This paper describes the choice of the Flemish waterway authority – De Vlaamse Waterweg – for a new vision on remote operation of its inland waterway infrastructure. From now on, remote control is the default operation mode. As of 2019, a new vision was approved to remotely control all our movable structures (ca.330) by 2032 from 3 remote control centres. The innovative aspect is that they will function as a fully interconnected meshed network and can be used as a back-up for each other. At first glance this may seem a purely technical challenge. It is however shown that by pursuing this goal, it compels us to rethink large parts of our organisation in regards with change management, business processes, roles and responsibilities, training and technical management. At the same time, we see society opportunities revealing themselves. This paper is aimed at sharing our experiences and as a call-to action for other waterway authorities, academic institutions and private companies to help envision and built the future waterway-systems.
Monitoring the Variation of Drought-Flood Abrupt Alternation and Its Response to Atmospheric Circulation at Multi-time Scales
Authors: Shi Wuzhi , Zhang Ke , Xie Yuebo , Chao Lijun , Tola Tolossa Lemma , Xue Xianwu
Published: February 2023

As an emerging disaster, the drought-flood abrupt alternation (DFAA) may cause unprecedented socio-economic impacts under changing environment, which has attracted extensive attention in recent decades. DFAA involves drought to flood (DTF) and flood to drought (FTD). However, thus far, little effort has been made to identify DFAA with high spatial resolution. Moreover, few studies have fully revealed the driving mechanisms of DFAA by large-scale climate factors. Here, the Yellow River Basin (YRB) was selected as the research area, which is an important agricultural base in China. The spatiotemporal characteristics of DFAA at multiple time scales during flood season were analyzed using 0.25° grid precipitation from 1961 to 2020 in the YRB. Furthermore, the Pearson correlation method and cross wavelet method were used to investigate the relationship between circulation anomaly (such as Arctic oscillation (AO), Pacific decadal oscillation (PDO), El Niño Southern Oscillation (ENSO), and sunspot) and DFAA to explore the potential causes of DFAA in this region. The results demonstrated that: (1) FTD trend in the YRB is serious, and the short period of FTD trend is June-July > July-August > August-September; (2) spatially, the high-frequency long-period DFAA was distributed in the whole YRB, while the DFAA in June-July and July-August were concentrated in the center of the YRB; (3) AO and PDO are the key factors to induce DFAA in the YRB, especially the changes of AO and PDO phase. This study helps improve our understanding of the relationship between DFAA and large-scale climate factors and provides new insights for future disaster assessment.
Construction of Container Terminal in the Yangon River
Authors: Kohno Hiroki , Takahashi Masayuki , Niina Daisuke , Tokiwa Satoshi
Published: February 2023

The Port of Yangon is the largest port in Myanmar and a river port located approximately 40 km upstream from the Yangon estuary. The country’s economic growth has led to the construction of a new container terminal in the Thilawa area, 16 km downstream from the Yangon port. Regardless of the difficult natural conditions in the area, project had to be completed in a short period at the request of the client. In order to shorten the construction period, construction of a jetty using the jacket method and soil improvement combined with the consolidation acceleration method were adopted. After repeated studies, the project was completed in a short period of 915 days. This paper describes the details of these studies.
Analysis on the Characteristics of Channel Scour and Deposition in the Nanjing Reach of the Yangtze River After Impoundment of the Three Gorges Reservoir
Authors: Wang Nairu , Huang Suning , Cao Shuang , Zhang Hongyu , Zhang Taotao
Published: February 2023

The construction and operation of the Three Gorges reservoir (TGR) alters the water and sediment conditions in the downstream channels, rendering the sediment transport capacity of water flow in these downstream channels at an unsaturated state, subsequently leading to scour and affecting flood prevention. Therefore, this study statistically analyzed the variations of channel scour and deposition in the Nanjing reach since the operation of the TGR, using the measured hydrologic and channel topographic data. The results showed that, the scour in the Nanjing reach was weak during 2001–2006, but prominently intensified during 2006–2020, with the multi-year average bankfull channel scour amount being 745.5 × 104 m3/a for the entire Nanjing reach. For the period of 2020.11–2021.03 after the basin-scale big flood in 2020, the scour was further intensified, with the total bankfull channel scour amount reaching 2677 × 104 m3. Since 2006, the Nanjing reach demonstrated an overall trend of “scour in both main channel and floodplain”, and bankfull channel scour was dominant, with the scour amount being 85% of that of the flood channel scour amount. Furthermore, scour was more intense on the left bank than on the right bank. The left branch of Xinjizhou reach and its downstream reaches were all erosional, demonstrating a pattern of scour amount being larger in the upper reach and smaller in the lower reach. Also, the multi-year average scour amount was the greatest at the Longtan and Yizheng reach, while the multi-year average scour intensity was the strongest at the main reach upstream the Meizizhou bifurcated reach.
Impact of Three Gorges Project (TGP) on Riverbed Revolution and Navigation Conditions in the Taipingkou Waterway
Authors: Yang Qilin , Shang Qianqian , Xu Hui , Xu Min
Published: February 2023

Taipingkou channel is the first sandy shoal channel in the lower reaches of the Three Gorges Project (TGP). The change of river boundary is basically stable under human control, but the change of beach trough in the channel is complex, which has adverse effects on navigation. In particular, the shrinkage of Sanbatan is harmful to the design of navigation bridge hole of Jingzhou Yangtze River Bridge in dry season. By analyzing the hydrological and sediment characteristics of Taipingkou waterway before and after the impoundment of the Three Gorges Project, and studying the changes of river regime, erosion and deposition adjustment, beach evolution and diversion ratio, the influence of the impoundment of the Three Gorges Project on the riverbed evolution of Taipingkou waterway is discussed. The results show that the Three Gorges Project has changed the inflow and sediment process of Taipingkou Waterway, resulting in the frankness of annual runoff process and the reduction of sediment concentration. Under the condition of new water and sediment, the tidal flats of Taipingkou waterway show a general erosion trend. The branch with large drawdown and good inflow conditions is easier to develop, and the peak regulation greatly limits the back siltation of the convex bank side beach in the recession period. It is believed that the root cause of the current navigation obstruction of Taipingkou waterway is that the navigation bridge hole setting of Jingzhou Yangtze River Bridge cannot adapt to the trend of river evolution, and dredging is an effective measure to ensure the smooth flow of the waterway.
On Characterizing Flow Resistance in a Tidal Reach
Authors: Jing Ye , Lei Xueting , Qin Jie , Wu Teng , Agbemafle Elikplim
Published: February 2023

The tidal reaches are characterized by unsteady and non-uniform flow (UNF), which is significantly different from the commonly assumed steady and uniform flow (SUF) in hydraulics. The SUF shows invariant temporal and spatial flow characteristics, and thus flow acceleration is absent in a prismatic channel. However, for the UNF, the variation of flow velocity and depth in both temporal and spatial scales causes the loss of flow energy, and thus increases the flow resistance. In order to clarify the variation of flow resistance and its influencing factors in tidal reaches, this study investigates the flow resistance characteristics under UNF conditions. In this study, a typical tidal section of the Lower Yangtze River (LYR) – Kouanzhi Waterway (KW) – was selected as the study area, where the temporal variation of water surface along the river course at different tide levels, the bathymetry of multiple cross-sections, the distribution of cross-sectional flow velocity and its temporal variation were measured in detail. Based on these field measurement data, the contribution terms to the energy slope were calculated and evaluated, by decomposing the momentum equation. The calculated contributing terms include water surface gradient, local acceleration, and convective acceleration. The results showed that the local acceleration and convective acceleration have a substantial impact on the energy slope during specific time periods, which was found to be more significant than the findings in previous studies. The results show that the local acceleration term is more significant than the convective acceleration term except when the water surface slope is close to zero, and its contribution is significant throughout the flood tide and the initial ebb tide periods. The above research results are of great significance for the investigation of flow resistance mechanisms and numerical simulations in tidal rivers.
Spatiotemporal Evolution Characteristics and Influencing Factors of Incoming Water and Sediment in Three Gorges Reservoir
Authors: Chen Peng , Lu Jinyou , Jin Zhongwu , Zhou Yinjun , Tang Rouxin , Liu Zhaoxi , Han Qiuba
Published: February 2023

Based on the hydrological and sediment observation data of the main stream and main stream of the upper Yangtze River from 1956 to 2018, using M-K test, Wavelet analysis, Approximate entropy and Lyapunov exponent, this paper analyzes the spatiotemporal evolution characteristics from the perspectives of catastrophe, periodicity, complexity and chaos of incoming water and sediment in The TGR (TGR), defines the connotation of “new water and sediment conditions” in the TGR, and discusses the main influencing factors of spatiotemporal variation of incoming water and sediment in the TGR. The results show that: (1) Except Pingshan station of Jinsha River, Fushun station of Tuojiang River and Wulong station of Wujiang River, the runoff of other main and tributaries and TGR in the upper Yangtze River has no significant change, but the sediment discharge has obvious mutation, and the runoff and sediment have periodic changes in different degrees; (2) The complexity of annual runoff and sediment transport in the TGR increases gradually, and the complexity of sediment transport is greater than that of runoff. Both annual runoff and sediment transport are chaotic, and the complexity of runoff and sediment transport sequence increases gradually from the upper reaches to the lower reaches; (3) The connotation of “new water and sediment condition” shows that there is no obvious mutation in runoff and sediment transport in time scale, the main cycle of water and sediment change is basically the same, and the complexity and chaos of sediment transport in space scale are significantly greater than runoff, and the change degree of sediment transport is more significant than runoff; (4) From 1991 to 2002, climate change (rainfall) was an important factor affecting the sediment discharge in the upper Yangtze River. From 2003 to 2018, the impact of climate change was relatively insignificant, and human activities became the most important factor.
Study on Classification Arrangement and Hydraulic Characteristics of Water-Saving Ship Lock Under Ultra-high Head
Authors: Zhu Long , Wang Xiaodong , Huang Yue , Liu Benqin , Li Zhonghua
Published: February 2023

The ship lock with water saving basins can store part of water during the operation, which has the outstanding advantage of saving water resources. At the same time, the water-saving ship lock can divide the total water head into stages, significantly reduce the operating head of each stage, which can provide technical conditions for simplifying the ship lock’s filling & emptying system and improving the operating conditions of lock’s valves. For ship lock with high head and large water level variation, the layout of the saving basins and the division of water level are very important. They determine the overall layout, operation efficiency and safety performance of the ship lock. With the increase of water head and water level variation, the classification arrangement of water-saving ship lock will become very complex. Therefore, based on the Baishi water-saving ship lock project (60 m-class, ultra-high head), the analysis and calculation research are carried out in this paper. First of all, the influence laws of key factors such as water-saving rate, number of water saving basins, area of water saving basins and operating head on water level division are obtained. On this foundation, a reasonable water level classification scheme for 60m-class ship lock is proposed, and the hydraulic characteristics of ship lock under different operating conditions are analyzed, and the feasibility of ship lock layout scheme is demonstrated. The research results can provide direct technical support for Baishi ship lock project, and provide reference for the design and construction of similar water-saving ship lock projects.
Technical Status Evaluation of River Training Works Based on the Improved DS Evidence Theory
Authors: Jiang Zhonglian , Chu Xiao , Yu Zhen , Guo Jianqun , Chu Xiumin
Published: February 2023

A large number of river training works have been built in the inland waterway regulation projects to improve ship navigation conditions. However, water damages to river training works happen frequently in practice. Technical status evaluation of river training works is regarded as a fundamental content of inland waterway maintenance. Due to the various influencing factors and complex mechanisms, the content involved in the standard files is recognized as qualitative and no quantitative evaluation method is recommended so far. The technical status of river training works is currently evaluated through on-site investigation which is time-consuming and individual-dependent. By means of multi-source sensors, massive status data of river training works could be obtained instantaneously. Study on the technical evaluation model based on the multi-source information fusion theory attracts more attention in recent years. The classical DS evidence theory could fail as evidence conflict occurs. Thus, the Pearson’s correlation coefficient is calculated and utilized to update the probability distribution in the present study. A novel technical status evaluation model based on the improved DS evidence theory is established. The model is further verified through three case studies of traditional river training works (spur dike and flexible mattress belt) in the Yangtze River, China. The model outputs are consistent with the technical survey reports as well as the published research article. Quantitative and accurate evaluation of river training works could be accomplished by applying the proposed evaluation model. Moreover, the model could be embedded in the Inland Electronic Chart Display and Information System. The present study would provide theoretical basis for inland waterway maintenance and infrastructure monitoring in the future.
Shoreside Power at Berths for Inland Navigation Vessels – How to Make Available a Harmonised System of Shoreside Power Access on the Rhine to Reduce Air and Noise Pollution
Authors: Wisselmann Raphaël , Kempmann Kai
Published: February 2023

The Central Commission for the Navigation of the Rhine (CCNR) is an international organisation that exercises an essential regulatory role in the navigation of the Rhine. It is active in the technical, legal, economic and environmental fields. In all its areas of action, its work is guided by the efficiency of transport on the Rhine, safety, social considerations, and respect for the environment. Many of the CCNR’s activities now reach beyond the Rhine and are directly concerned with European navigable waterways more generally.

So as to take into particular account the challenges of climate change, in 2018 the transport ministers of the Member States of the Central Commission for the Navigation of the Rhine (Germany, Belgium, France, the Netherlands, Switzerland) signed a declaration, the so-called Mannheim Declaration, to reassert the objective of largely eliminating greenhouse gases and other pollutants by 2050 and to task the CCNR to develop a roadmap to achieve these goals. These goals that are intended to protect the environment and the climate concern not only inland navigation vessels’ propulsion systems but also the on-board power supply for operating machinery, for example when at berth.

Last but not least, the conflicts over berths on the Rhine in city centres demonstrate that joint efforts are required to reduce or largely eliminate both pollutant and noise emissions. Supplying inland navigation vessels with shore power can play an important role in reducing emissions and noise and helps achieve the objectives of the Mannheim Declaration, while also securing attractive city centre berths for future generations of boatmen. Together with its stakeholders, the CCNR works on a regular basis to identify technical and regulatory gaps in standards and provisions, and proposes activities that aim at a harmonised implementation of shoreside power infrastructure on the Rhine.
Simulation Study to Assess the Maximum Dimensions of Inland Ships on the River Seine in Paris
Authors: Mansuy Marc , Candries Maxim , Eloot Katrien , Page Sebastien
Published: February 2023

Traversing the river Seine in Paris is challenging for inland navigation vessels due to the density and diversity of local traffic and the variety of manoeuvres to be encountered in a confined environment. The waterway authority, Voies Navigables de France (VNF), commissioned a study to assess the relevance of the current regulations when present and future vessels of varying types and dimensions cross Paris. This paper describes the use of fast time and real time simulations to assess the maximum dimensions of ships crossing the Seine in Paris. In a first phase, fast time simulations were executed with a track controller, which allowed to identify bottlenecks on the full length (12 km) of the river Seine in Paris. Based on those results, critical scenarios were selected to be tested on a full mission bridge simulator by skippers familiar with the crossing of Paris. Inspired by PIANC INCOM WG 141 Detailed Design and Safety and Ease Approaches, the main challenges related to the simulation setup and the assessment methodology are presented and discussed in this paper. The simulations have shown that the main bottlenecks are related to the succession of passages under narrow bridges with non-aligned openings. The maximum water levels for which safe passage is possible, were determined for each ship type and compared with the existing regulations. Finally, recommendations were formulated, which were then discussed with VNF, end users and stakeholders.
Study on Flow Distribution on Diversion Surface at the Head of Sandbar in Bifurcated Reach
Authors: Liu Wanli , Xin Weiyan
Published: February 2023

The rule of flow distribution in the diversion region at the head of sandbar of bifurcated reach is studied. The results show that there are diversion points and stagnation points in the diversion area at the head of sandbar in straight-bifurcated reach, and there exists diversion surface due to the difference between flow directions of surface and bottom in the diversion area at the head of sandbar in meandering-bifurcated reach. The concept of diversion surface is put forward through the study. It refers to the curved surface along vertical direction calculated according to the diversion ratio of two branches in the local reach of the head of sandbar in diversion area. Natural flow characteristics at the head of typical bifurcated reach in the middle reaches of the Yangtze River are studied based on the concept of diversion surface, and the layout principle of regulation project at the head of sandbar in bifurcated reach is put forward, that is, the project at the head of sandbar should be set near the relatively stable diversion surface if the diversion ratio of two branches is not planned to be changed, while the purpose can be achieved by deflecting the starting point of the project to one side if it is made to play the role of changing the diversion ratio of two branches. The proposal of the concept and calculation method of diversion surface provides a theoretical basis for the design and construction of location of regulation works in bifurcated reach.
Study on Prediction Method for Compression Scour Depth of River-Crossing Bridge
Authors: Shang Qianqian , Xu Hui , Zhang Jian
Published: February 2023

Riverbed deformation caused by river-crossing bridge construction can be divided into compression scour and local scour. Compared with local scour, fewer studies have been made on the compression scour caused by bridge piers. It is noteworthy that, the compression scour can lead to riverbed scour of the whole cross section along a bridge site, which is obviously detrimental to the bridge foundation safety. Based on a summary of existing research findings, a prediction model for the compression scour of bridge piers is constructed, and the model is applied in predicting the compression scour depth of Shiyezhou River Bridge in the lower reaches of the Yangtze River. Firstly, the pier boundary treatment methods at different spatial scales are discussed. Subsequently, the selection method of flow and sediment processes is proposed from the engineering safety point of view, according to the flow and sediment characteristics on the lower reaches of the Yangtze River. Finally, the depth of compression scour around the upstream and downstream of Shiyezhou Bridge piers are predicted, and comparisons were made between the prediction depth of Shiyezhou Bridge and other existing bridges in the lower reaches of the Yangtze River. Comparisons show that the compression scour depth of Shiyezhou Bridge was basically equivalent to that of other bridges downstream the Yangtze River. The results indicate that the method for predicting the compression scour depth of bridge piers is reasonable and feasible, and the prediction of compression scour depth can provide technical basis for determining the embedment depth of the bridge pier foundation.