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New insight into scale inhibition during tea brewing: Ca^(2+)/Mg^(2+) complexing and alkalinity consumption

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Journal of Environmental Sciences 2023年第2期124卷 901-914页

作者： linjun li Jinsuo Lu Heliang Pang Zhiqiang Zhang Jing Yang Pengpeng li Xiaoyu Yan Miaomiao Fan School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Green Building in West China Xi’an University of Architecture and TechnologyXi’an 710055China

Scale not only affects the taste and color ofwater,but also increases the risks of osteoporosis and cardiovascular diseases associated with drinking *** a popular beverage,tea is rich many substances that have considerable potential for scale inhibition,including protein,tea polyphenols and organic *** this study,the effect of tea brewing on scale formationwas *** was found that the proteins,catechins and organic acids in tea leaves could be released when the green tea was brewed in water with sufficient hardness and *** tea-released protein was able to provide carboxyl groups to chelate with calcium ions(Ca^(2+)),preventing the Ca^(2+)from reacting with the carbonate ions(CO_(3)^(2-)).The B rings of catechins were another important structure in the complexation of Ca^(2+)and magnesium ions(Mg2+).The carboxyl and hydroxyl groups on the organic acids was able to form fivemembered chelating rings with Ca^(2+)and Mg^(2+),resulting in a significant decrease in Ca^(2+)from 100.0 to 60.0 mg/***,the hydrogen ions(H^(+))provided by the organic acids consumed and decreased the alkalinity of the water from 250.0 to 131.4 mg/L,leading to a remarkable reduction in pH from 8.93 to *** further prevented the bicarbonate(HCO_(3)^(-))from producing CO_(3)^(2−)when the water was *** reaction of the tea constituents with the hardness and alkalinity inhibited the formation of scale,leading to a significant decrease in turbidity from 10.6 to 1.4 ***,this study provides information to help build towards an understanding of the scale inhibition properties of tea and the prospects of tea for anti-scaling in industrial applications.

关键词： Scale inhibition Tea brewing Chelation Hardness Alkalinity

The rise of non-vdW moiré superlattices

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The Innovation 2024年第6期5卷 35-36页

作者： Zicheng li Xinyu Duan Zehui Zhou linjun li Beibei Xu State Key Laboratory of Extreme Photonics and Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China

The formation of a moirésuperlattice is induced by the stacking of van der Waals(vdW)2D materials with a twist angle or small lattice *** superlattice functions as a periodic potential for electrons,forming moiréfla... 详细信息

关键词： superlattice twist bands

FGF8-mediated signaling regulates tooth developmental pace during odontogenesis

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Journal of Genetics and Genomics 2022年第1期49卷 40-53页

作者： Chensheng lin Ningsheng Ruan linjun li Yibin Chen Xiaoxiao Hu YiPing Chen Xuefeng Hu Yanding Zhang Fujian Key Laboratory of Developmental and Neural Biology and Southern Center for Biomedical Research College of Life SciencesFujian Normal UniversityFuzhouFujian 350117China Department of Cell and Molecular Biology Tulane UniversityNew OrleansLA 70118USA

The developing human and mouse teeth constitute an ideal model system to study the regulatory mechanism underlying organ growth control since their teeth share highly conserved and well-characterized developmental processes, and their developmental tempo varies notably. In the current study, we manipulated heterogenous recombination between human and mouse dental tissues and demonstrated that the dental mesenchyme dominates the tooth developmental tempo and FGF8 could be a critical player during this developmental process. Forced activation of FGF8 signaling in the dental mesenchyme of mice promoted cell proliferation, prevented cell apoptosis via p38 and perhaps PI3 K-Akt intracellular signaling,and impelled the transition of the cell cycle from G1-to S-phase in the tooth germ, resulting in the slowdown of the tooth developmental pace. Our results provide compelling evidence that extrinsic signals can profoundly affect tooth developmental tempo, and the dental mesenchymal FGF8 could be a pivotal factor in controlling the developmental pace in a non-cell-autonomous manner during mammalian odontogenesis.

关键词： FGF8 Tooth Developmental pace Non-cell-autonomous

Passively Q-switched diode-pumped Tm,Ho:LuVO4 laser with a black phosphorus saturable absorber

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Chinese Physics B 2019年第9期28卷 203-205页

作者： linjun li Tianxin li Long Zhou Jianying Fan Yuqiang Yang Wenqiang Xie Shasha li The Higher Educational Key Laboratory for Measuring&Control Technology and Instrumentations of Heilongjiang Province Harbin University of Science and TechnologyHarbin 150080China Heilongjiang Province Key Laboratory of Optoelectronics and Laser Technology&Heilongjiang Province Engineering Technology Research Center of Solid-state Laser Technology and Application Heilongjiang Institute of TechnologyHarbin 150050China

We presented a passively Q-switched(PQS) diode-pumped c-cut Tm, Ho:LuVO_4 laser with a black phosphorus saturable absorber for the first *** PQS mode, an average output power of 0.86 W and a peak power of 2.32 W were acquired from the Tm, Ho:LuVO4 laser with the pump power of 14.55 W, corresponding to a pulse width of 2.89 μs,a pulse repetition rate of 71.84 kHz, and a pulse energy of about 6.70 μJ.

关键词： passively Q-switched(PQS) technology Tm Ho:LuVO4 crystal pulse width

Polarized Water Driven Dynamic PN Junction-Based Direct-Current Generator

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Research 2021年第1期2021卷 469-478页

作者： Yanghua Lu Yanfei Yan Xutao Yu Xu Zhou Sirui Feng Chi Xu Haonan Zheng Zunshan Yang linjun li Kaihui liu Shisheng lin College of Microelectronics College of Information Science and Electronic EngineeringZhejiang UniversityHangzhou 310027China State Key Lab for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics Collaborative Innovation Center of Quantum MatterSchool of PhysicsPeking UniversityBeijing 100871China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication EngineeringSouth China Normal UniversityGuangzhou 510006China State Key Laboratory of Modern Optical Instrumentation Zhejiang UniversityHangzhou 310027China

There is a rising prospective in harvesting energy from the environment,as in situ energy is required for the distributed sensors in the interconnected information society,among which the water flow energy is the most potential candidate as a clean and abundant mechanical ***,for microscale and unordered movement of water,achieving a sustainable direct-current generating device with high output to drive the load element is still challenging,which requires for further ***,we propose a dynamic PN water junction generator with moving water sandwiched between two semiconductors,which outputs a sustainable direct-current voltage of 0.3 V and a current of 0.64μ*** mechanism can be attributed to the dynamic polarization process of water as moving dielectric medium in the dynamic PN water junction,under the Fermi level difference of two *** further demonstrate an encapsulated portable power-generating device with simple structure and continuous direct-current voltage output of 0.11 V,which exhibits its promising potential application in the field of wearable devices and the IoTs.

关键词： wear generating moving

Passively Q-switched operation of a 1.94μm thulium-doped solid-state laser based on MXeneV_(2)CT_(x)

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Chinese Optics Letters 2023年第2期21卷 40-44页

作者：袁晋鹤李佳睿吴政阳李双成韩杰李林军 College of Physical Science and Technology Heilongjiang UniversityHarbin 150080China Heilongjiang Provincial Key Laboratory of Laser Spectroscopy Technology and Application Harbin University of Science and TechnologyHarbin 150080China School of Data Science and Technology Heilongjiang UniversityHarbin 150080China

MXene V_(2)CT_(x) has great practicability because it is not easy to degrade under ambient *** this paper,a V_(2)CT_(x) saturable absorber(SA)was firstly applied to a passively Q-switched(PQS)laser,to the best of our *** V_(2)CT_(x)-SA was prepared by the spin-coating *** linear absorption of the V_(2)CT_(x)-SA in the 1000-2200 nm region and the nonlinear absorption near 2μm were *** the V_(2)CT_(x)-SA,a typical PQS operation at 1.94μm was realized in a Tm:*** minimum pulse width produced by the PQS laser was 528 ns,and the peak power,repetition rate,and average output power were 10.06 W,65.9 kHz,and 350 mW,***,the maximum pulse energy was 6.33μ*** work demonstrates that the V_(2)CT_(x) can be used as an effective SA to obtain nanosecond pulses with high peak power and high repetition rate simultaneously.

关键词： passive Q-switching MXene V2CTx saturable absorber thulium doping

基于实验经济学的中介价格信息掌握对二手房议价效率影响

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清华大学学报（自然科学版） 2017年第4期57卷 421-425,431页

作者：张红李林峻李维娜清华大学恒隆房地产研究中心北京100084 清华大学城镇化与产业发展研究中心北京100084 香港恒生管理学院会计系香港999077

研究中介价格信息掌握对二手房议价效率的影响有助于提升中介服务质量,推动二手房市场的健康发展。该文基于实验经济学研究了中介价格信息掌握对二手房议价效率的影响。提出中介价格信息掌握程度的测算公式,从买方、卖方、中介及总体的... 详细信息

研究中介价格信息掌握对二手房议价效率的影响有助于提升中介服务质量,推动二手房市场的健康发展。该文基于实验经济学研究了中介价格信息掌握对二手房议价效率的影响。提出中介价格信息掌握程度的测算公式,从买方、卖方、中介及总体的角度确定二手房议价效率的评价方式,结合现实二手房市场特点,设计并实施二手房议价实验,利用实验数据对中介价格信息掌握程度和二手房议价效率之间的影响关系进行分析。研究结果表明:中介价格信息掌握程度对买方议价效率没有显著影响,提高中介价格信息掌握程度能够显著提升卖方议价效率、中介议价效率和总体议价效率;中介价格信息掌握程度每提高1%,将推动卖方议价效率、中介议价效率、总体议价效率分别上升2.27%、0.69%、0.73%。

关键词：价格信息掌握二手房议价效率实验经济学

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微纳光纤及其锁模激光应用

光学学报 2019年第1期39卷 181-199页

作者：王利镇李林军童利民浙江大学光电科学与工程学院现代光学仪器国家重点实验室浙江杭州310027

微纳光纤是一种直径接近或小于传输光波长的纤维波导,由于纤芯和包层折射率差较大,具有强光场约束、强倏逝场、低损耗、反常波导色散、表面均匀性好和机械性能高等特性。近年来,以纳米材料作为饱和吸收体的被动锁模激光器成为超短脉冲... 详细信息

微纳光纤是一种直径接近或小于传输光波长的纤维波导,由于纤芯和包层折射率差较大,具有强光场约束、强倏逝场、低损耗、反常波导色散、表面均匀性好和机械性能高等特性。近年来,以纳米材料作为饱和吸收体的被动锁模激光器成为超短脉冲激光技术方向的研究热点。得益于微纳光纤的强光场约束能力及大比例倏逝场,纳米材料与微纳光纤的复合结构能显著增强光与物质的相互作用,进而降低该复合结构的饱和吸收阈值,为超短脉冲产生和非线性动力学等研究提供一个新颖而灵活的平台。同时,微纳光纤因具有反常波导色散、光谱滤波、饱和吸收和偏振敏感等特性,在激光器的色散调控、偏振锁模等方面获得应用。介绍了微纳光纤的制备和特性以及在锁模激光方面的典型应用和相关技术的最新进展,并就未来的发展方向进行了展望。

关键词：微纳光纤锁模激光器饱和吸收体色散调控

汽车用ZL101铝合金复合稀土变质与热处理工艺研究

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热加工工艺 2023年第15期52卷 86-88页

作者：李林峻河南工程学院工程训练中心河南郑州2491191

采用显微组织观察、拉伸试验研究了ZL101铝合金的Ce-La复合稀土(Ce含量65%,La含量35%)变质与热处理工艺。结果表明:添加0.05%复合稀土对ZL101铝合金进行变质处理,可以有效减小合金中α-Al二次枝晶间距,细化共晶Si组织;与未变质的ZL101... 详细信息

采用显微组织观察、拉伸试验研究了ZL101铝合金的Ce-La复合稀土(Ce含量65%,La含量35%)变质与热处理工艺。结果表明:添加0.05%复合稀土对ZL101铝合金进行变质处理,可以有效减小合金中α-Al二次枝晶间距,细化共晶Si组织;与未变质的ZL101铝合金相比,变质处理的ZL101铝合金的抗拉强度、屈服强度和伸长率分别提高了6.5%、4.5%和47.1%。对其进行540℃×4 h固溶+170℃×8 h时效处理后,ZL101铝合金组织中共晶Si相呈颗粒状,均匀分布在晶界处,其抗拉强度、屈服强度和伸长率分别达到306 MPa、231 MPa和6.3%,综合力学性能匹配最好。

关键词： ZL101铝合金变质处理热处理工艺显微组织力学性能