检索结果-南通市图书馆

Journal of Environmental Sciences 2024年第8期142卷 115-128页

作者： Yijun Duan Fang liu Xiang liu Miao Li School of Environment Tsinghua UniversityBeijing 100084China Transportation Institute of Inner Mongolia University Hohhot 010070China

Microscale zero-valent iron(mZVI)has shown great potential for groundwater Cr(Ⅵ)***,low Cr(Ⅵ)removal capacity caused by passivation restricted the wide use of *** prepared mZVI/GCS by encapsulating mZVI in a porous glutaraldehydecrosslinked chitosan matrix,and the formation of the passivation layer was alleviated by reducing the contact between zero-valent iron *** average pore diameter of mZVI/GCS was 8.775 nm,which confirmed the mesoporous characteristic of this *** of batch experiments demonstrated that mZVI/GCS exhibited high Cr(Ⅵ)removal efficiency in a wide range of pH(2-10)and temperature(5-35℃).Common groundwater coexisting ions slightly affected m ZVI/*** material showed great reusability,and the average Cr(Ⅵ)removal efficiency was 90.41%during eight *** this study,we also conducted kinetics and isotherms ***-second-order model was the most matched kinetics *** Cr(Ⅵ)adsorption process was fitted by both Langmuir and Freundlich isotherms models,and the maximum Langmuir adsorption capacity of m ZVI/GCS reached243.63 mg/g,which is higher than the adsorption capacities of materials reported in most of the previous ***,the column capacity for Cr(Ⅵ)removal of a mZVI/GCS-packed column was 6.4 times higher than that of a mZVI-packed column in a 50-day ***,mZVI/GCS with a porous structure effectively relieved passivation problems of mZVI and showed practical application prospects as groundwater Cr(Ⅵ)remediation material with practical application prospects.

关键词： Chitosan Glutaraldehyde mZVI Cr(Ⅵ) Groundwater

Thermoregulatory molecular sieving in crystals

在线全文

学校读者我要写书评

暂无评论

Science China Materials 2024年第10期67卷 3419-3420页

作者： Guozhen liu Wanqin Jin Gongping liu State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211800China

Sub-nanometer channels for the selective recognition of the components in chemical mixtures from others play a crucial role in the adsorption and membrane separation[1].It remains a grand challenge to separate small m... 详细信息

关键词： structure. molecular separation

Towards cultivar-oriented gene discovery for better crops

在线全文

学校读者我要写书评

暂无评论

The Crop Journal 2024年第3期12卷 670-675页

作者： Dengcai liu Triticeae Research Institute Sichuan Agricultural UniversityChengdu 611130SichuanChina

The continued expansion of the world population,increasingly inconsistent climate and shrinking agricultural resources present major challenges to crop ***,the increasing ability to discover and manipulate genes creates new opportunities to develop more productive and resilient *** genes have been described in papers as being beneficial for yield ***,few of them have been translated into increased yield on *** contrast,commercial breeders are facing gene decidophobia,i.e.,puzzled about which gene to choose for breeding among the many identified,a huge chasm between gene discovery and cultivar *** purpose of this paper is to draw attention to the shortfalls in current gene discovery research and to emphasise the need to align with cultivar *** methodology dictates that genetic studies not only focus on gene discovery but also pay good attention to the genetic backgrounds,experimental validation in relevant environments,appropriate crop management,and data *** close of the gaps should accelerate the application of molecular study in breeding and contribute to future global food security.

关键词： Cultivar innovation Data reusability Gene discovery Gene decidophobia Omnigenic model

Fatigue-resistant sliding ferroelectricity

在线全文

学校读者我要写书评

暂无评论

Science China Materials 2024年第10期67卷 3417-3418页

作者： Zheng liu School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore

The direction of spontaneous polarization in ferroelectricity can be reoriented by an external electric *** special feature of ferroelectricity is important candidates for fabricating advanced nonvolatile random-access memory[1].However,repeatedly switching polarization induces the ferroelectric device performance degenerates due to a reduction of polarization.

关键词： polarization ferroelectric field.

A REFINEMENT OF THE SCHWARZ-PICK ESTIMATES AND THE CARATHéODORY METRIC IN SEVERAL COMPLEX VARIABLES

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2024年第4期44卷 1337-1346页

作者： Xiaosong liu Taishun liu School of Mathematics and Statistics Lingnan Normal UniversityZhanjiang 524048China Department of Mathematics Huzhou UniversityHuzhou 313000China

In this article,we first establish an asymptotically sharp result on the higher order Fréchet derivatives for bounded holomorphic mappings f(x)=f(0)+∞∑s=1Dskf(0)(x^(sk))/(sk)!:B_(X)→B_(Y),where B_X is the unit ball of *** next give a sharp result on the first order Fréchet derivative for bounded holomorphic mappings F(X)=F(0+)∞∑s=KD^(s)f(0)(x^(8)/s!):B_(X)→B_(Y),where B_(X)is the unit ball of *** results that we derive include some results in several complex variables,and extend the classical result in one complex variable to several complex variables.

关键词： refined Schwarz-Pick estimate bounded holomorphic mapping Carathéodory metric first order Fréchet derivative higher order Fréchet derivatives

Breakdown of effective medium theory:A study of photonic spin Hall effect in deep-subwavelength all-dielectric multilayers

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 173-174页

作者： Yongmin liu Department of Mechanical and Industrial Engineering Northeastern UniversityBoston 02115USA Department of Electrical and Computer Engineering Northeastern UniversityBoston 02115USA

Effective medium theory(EMT)has been widely applied in material science,electromagnetics and photonics to determine the effective material properties for inhomogeneous composites comprising subwavelength *** versatility of this foundational approach has been established through its application in classical Maxwell-Garnet models,which encompass relatively simple structures。

关键词： composites theory dielectric

The important role of Turbidity Maximum Zone in sedimentary dynamic of estuarine mangrove swamp

在线全文

学校读者我要写书评

暂无评论

Frontiers of Earth Science 2024年第1期18卷 219-226页

作者： Tao liu Ying liu Baoqing HU Key laboratory of Environment Change and Resources Use in Beibu Gulf(Ministry of Education) Nanning Normal UniversityNanning 530001China School of Civil Engineering and Architecture Guangxi UniversityNanning 530004China

Sedimentation is a key process affecting wetland sustainability and carbon burial *** context of sea level rise,climate change and human activities,further understanding about the sedimentary dynamic in wetland is critical in predicting the landscape evolution or the change in carbon burial *** this study,based on the field hydrological observation in a mangrove system in the Nanliu River estuary,we found the net flux of suspended sediment to mangrove is 39−72 kg/m in tidal cycles with Turbidity Maximum Zone(TMZ)forming in surface layer and only is 9−18 kg/m in tidal cycles without *** higher net flux of suspended sediment to mangrove in tidal cycles with TMZ forming in surface layer is attributed to high SSC in rising tide and intense flocculation in *** significant discrepancy in sedimentation rate in the mangrove patches also can be explained by the probability of TMZ forming in the surface layer of *** future,rapid sea level rising may lead to the change of TMZ pattern in estuary,which will result in non-negligible variation in sedimentation rate in *** to the present data of sedimentation rate in wetlands,the fragility of wetlands in river estuary may be miscalculated.

关键词： mangrove wetland sedimentation Turbidity Maximum Zone Nanliu River

A compact bimorph rotary piezoelectric actuator with customized small power supply

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第4期67卷 1185-1195页

作者： DENG Jie liu DaQing WANG WeiYi liu YingXiang School of Mechatronics and Engineering Harbin Institute of TechnologyHarbin 150001China

Inertial piezoelectric actuators are widely applied in precision devices with simple structure and accurate ***,existing inertial piezoelectric actuators still face the challenges of rollback motion and bulky power *** this work,an alternate excitation strategy and a customized small power supply for a bimorph rotary piezoelectric actuator(BRPA)are proposed to solve the *** BRPA prototype is designed with a bipedal symmetrical structure,measuring 35 mm in height and 32 mm in diameter,which has a maximum rotation velocity of 0.247 rad/s and a resolution of 0.66μ*** to the bipedal symmetrical structure,the friction directions between the driving feet and the rotor can be coordinated to suppress the *** rollback ratio is almost zero when the phase difference of the exciting signal is set as 180°.The customized power supply is designed and manufactured,whose size is 58 mm×56 mm×46 *** can output signals for the single step mode and the continuous mode,and they are adopted to excite BRPA to achieve a small stroke with one single step and a large stroke with continuous step,***,an experimental system for optical fiber alignment is developed based on the BRPA and the customized small power supply,the experiment has verified the practicability of this work in the precision fields,especially in the miniaturized precision systems.

关键词： inertial piezoelectric actuator customized small power supply single step mode continuous mode rollback suppression miniaturized precision system

Compact multilayer liquid crystal polymer lowpass filter with 8-shaped inductor

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2024年第3期31卷 80-86页

作者： liu Weihong Wang Guoxiu liu Qingran School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

Lumped element lowpass filter(LPF)for ultra-high frequency(UHF)radio frequency(RF)front-end system is presented based on multilayer liquid crystal polymer(LCP).The lumped element LPF can achieve miniaturization and one transmission zero on the stopband by the 8-shaped *** lumped element LPF is fabricated on a 4-layer LCP substrate with a compact size of 9 mm×14 mm×0.193 *** measured cut off frequency of the lumped element LPF is 0.5 GHz with insertion loss(IL)less than 0.37 *** measured and simulated results suggest that it is a possible candidate for the application of UHF RF front-end system.

关键词： lowpass filter(LPF) multilayer liquid crystal polymer(LCP) miniaturization 8-shaped inductor

High-performance nickel metal hydride battery anode with enhanced durability and excellent low-temperature discharge capability

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第10期17卷 8819-8825页

作者： Zhitao Chen Huitian liu Jean Nei Nian liu School of Chemical and Biomolecular Engineering Georgia Institute of TechnologyAtlantaGA 30332USA GP Batteries HongkongChina

Current AB_(5)-type hydrogen storage alloys employed in nickel-metal hydride(NiMH)batteries exhibit exceptional low-temperature discharge performance but suffer from limited cycle life and insufficient high-temperature *** overcome these challenges,we introduce a hydrothermal synthesized LaF_(3)coating layer on the surface of the AB_(5)anode *** LaF_(3)coating layer adds a protective barrier for the active material,significantly improving the battery's cycle life and high-temperature *** findings indicate that(1)the LaF_(3)coated anode demonstrates an extended cycle life with increased specific capacity and a capacity retention of 88%after 40 cycles of abusive overcharging and rapid discharging at room temperature.(2)The synthesized anode exhibits a 97%recovery of its specific capacity of 292.7 mAh/g following 144 h of high-temperature storage.(3)The low-temperature discharge capacity of the synthesized anode remains on par with the pristine AB_(5)alloy at 230.4 mAh/g in a-40℃*** research presents a significant advancement in hydrogen storage alloy coatings and offers valuable insights for designing electrodes in NiMH batteries.

关键词： nickel metal hydride(NiMH)batteries hydrothermal synthesis lanthanum fluoride discharge capacity low temperature