低电压低功耗CMOS温度传感器

本发明提供一种低电压低功耗CMOS温度传感器，作为基于工作在亚阈值区的串联的场效应晶体管设计的超低功耗嵌入式CMOS温度传感器，特别适用于无源RFID在食物检测中的应用。使用串联的工作在亚阈值区的场效应晶体管作为传感元件进一步减小所需工作电压，进而减小功耗，这对无源RFID应用来说非常重要。温度传感器是无源RFID标签的一部分，其包含温度传感器前端、PTAT和CTAT延迟发生器、时间数字差分输出电路。在优选实施例中，该传感器嵌入于无源超高频RFID标签，此标签采用传统0.18μm 1P6M CMOS工艺制备而成。传感器前端的工作电压在0.5V以内，其数字接口的工作电压在1V以内。该传感器在33次样本/秒时所测得的总功耗为119纳瓦，其校准后在-10℃至30℃之间可达到的精度为+1/-0.8℃

The complex effects of ocean acidifiaction on the prominent N2-fixing cyanobacterium Trichodesmium

海洋浮游植物贡献了地球上约50%的初级生产力，驱动着海洋生物泵将碳从上层海洋向深层输出，在海洋和全球碳循环中扮演着举足轻重的角色，调节着全球气候。氮是浮游植物生长所必需的元素，其缺乏限制了全球面积一半以上海区的初级生产力。束毛藻是海洋生态系统中“新氮”的重要来源之一，可贡献高达50%的全球海洋总固氮量，对海洋初级生产力以及碳、氮生物地球化学循环起着至关重要的影响。 该研究以海洋生态系统中重要的“新氮”贡献者——束毛藻（Trichodesmium）为对象，通过系统性的实验室机理探究和海上现场实验，发现因大气CO2上升而引起的海洋酸化抑制束毛藻的固氮作用，且该负效应随着海水中铁浓度的下降而加剧。这一研究成果不仅揭示了海洋酸化对束毛藻的影响及其机制，而且为先前国际上就该科学问题的争议提供了科学解释，对于深入理解全球变化下碳、氮的海洋生物地球化学循环具有重要的意义。 史大林教授为论文的通讯作者，其课题组成员洪海征副教授为论文第一作者，研究助理沈容、博士生张福婷和温作柱等为研究骨干；论文的合作者还包括来自我实验室和美国佛罗里达州立大学、普林斯顿大学的科学家。【Abstract】Acidification of seawater caused by anthropogenic carbon dioxide (CO2) is anticipated to influence the growth of dinitrogen (N2)–fixing phytoplankton, which contribute a large fraction of primary production in the tropical and subtropical ocean. We found that growth and N2-fixation of the ubiquitous cyanobacterium Trichodesmium decreased under acidified conditions, notwithstanding a beneficial effect of high CO2. Acidification resulted in low cytosolic pH and reduced N2-fixation rates despite elevated nitrogenase concentrations. Low cytosolic pH required increased proton pumping across the thylakoid membrane and elevated adenosine triphosphate production. These requirements were not satisfied under field or experimental iron-limiting conditions, which greatly amplified the negative effect of acidification.该研究工作得到了中组部“青年千人计划”、国家自然科学基金委“优秀青年科学基金”和面上项目、国家重点研发计划等的资助

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies

Prediction of Energy Resolution in the JUNO Experiment

International audienceThis paper presents the energy resolution study in the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3% at 1 MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components of the JUNO detector. Various factors affecting the detection of inverse beta decay signals have an impact on the energy resolution, extending beyond the statistical fluctuations of the detected number of photons, such as the properties of liquid scintillator, performance of photomultiplier tubes, and the energy reconstruction algorithm. To account for these effects, a full JUNO simulation and reconstruction approach is employed. This enables the modeling of all relevant effects and the evaluation of associated inputs to accurately estimate the energy resolution. The study reveals an energy resolution of 2.95% at 1 MeV. Furthermore, the study assesses the contribution of major effects to the overall energy resolution budget. This analysis serves as a reference for interpreting future measurements of energy resolution during JUNO data taking. Moreover, it provides a guideline in comprehending the energy resolution characteristics of liquid scintillator-based detectors