科研成果

2017
Liu T, Lacy J, Li PS, Wang K, Qin S-L, Zhang Q, Kim K-T, Garay G, Wu Y, Mardones D, et al. ALMA Reveals Sequential High-mass Star Formation in the G9.62+0.19 Complex. \apj. 2017;849:25.
Deng H, Voltolini M, Molins S, Steefel C, DePaolo D, Ajo-Franklin J, Yang L. Alteration and erosion of rock matrix bordering a carbonate-rich shale fracture. Environmental science & technology. 2017;51:8861–8868.
Wu C-Y. Amastrian High Priests: Leading Men of the Koinon of the Cities in Pontus?, in Annual Meeting of Postgraduates in Ancient History (AMPAH). King’s College London, Strand campus, London; 2017.Abstract
This paper studies the high priests found in inscriptions from Amastris concerning the Koinon of the Cities in Pontus (henceforth “the Koinon”), commonly recognized as an assembly of cities in coastal Paphlagonia (Marek 2003, Vitale 2012; contra Loriot 2006).  The Amastrian high priests (7 in total) comprise of three types: 1) ἀρχιερεὺς τοῦ Πόντοῦ, which can be securely associated with the Koinon; 2) ἀρχιερεύς, without specific designation as to what sort of imperial or local cult it was in charge; 3) ὁ τοῦ ἐπουρανίου Θεοῦ Σεβαστοῦ ἀρχ[ιερεὺς διὰ βίου, which also has the Latin equivalent Divi Aug. perpetuus sacerdos inscribed together as a bilingual text.  Should all three types titles be interpreted as the same office? Christian Marek (2003) assumed that they were: he included 2) and 3) under 1), without clarification. Xavier Loriot (2006) assumed differently: in his tabulation of dignitaries of Pontus, he omitted the office holders of 2) and 3), and he also did not state his rationale.  The discrepancy is significant because of dating. Time-reckoning markers on inscriptions of 2) and 3) help date the former to 62 CE, and the latter c. 50 CE, all considerably earlier than the earliest inscription in 1), which is Trajanic. The problem, on the other hand, is that Marek’s inclusion of 2) and 3) may be wrong: Frija (2012) demonstrated that when a high priesthood was not specified, they could be instead high priests of the municipal imperial cult.  This paper considers the possibility that 2) and 3) may have been local/municipal office(s), and could have been the precursor to the High Priesthood of Pontus. Particular emphasis will be on the bilingual text of 3), which contain the surprising attribution ἐπουρανίος, commonly associated with Zeus or Theos Hypsistos and without a Latin equivalent.
Zhang B, Zhao B, Zuo P, Huang Z, Zhang J. Ambient peroxyacyl nitrate concentration and regional transportation in Beijing. Atmospheric Environment [Internet]. 2017;166:543-550. 访问链接Abstract
Peroxyacyl nitrates (PANs) are photochemical secondary pollutants that play a key role in the atmospheric chemistry of the troposphere. However, there have been few studies on the long-term variation and inter-regional transport of PANs. In this study, summertime ambient PAN concentrations were monitored at urban and rural sites in Beijing and Hebei, China, between 2006 and 2014. In Beijing, the peak concentrations of PAN and PPN were in the range of 6–17 ppbv and 0.6–2.2 ppbv, respectively, higher than concentrations in other provinces. The nitrogen oxide (NOx) concentration decreased at a rate of 1.7 ppbv/yr (∼4% yr−1), and the PAN concentration decreased at a rate of 0.03 ppbv/yr (∼3% yr−1), while the ozone (O3) concentration increased at a rate of 1.5 ppbv/yr (∼4% yr−1). Trajectory clustering analyses showed that high concentrations of PAN were mainly affected by low air masses transported medium/short distances from South Beijing, and the potential source contribution function maps showed that the likely pollution source area was concentrated in the southern region of Beijing. These findings provide a theoretical basis for pollution control in this region.
Sun W, Li Y, Xiao Y, Zhao Z, Ye S, Rao H, Ting H, Bian Z, Xiao L, Huang C, et al. An ammonia modified PEDOT: PSS for interfacial engineering in inverted planar perovskite solar cells. ORGANIC ELECTRONICS. 2017;46:22-27.
Sun W, Li Y, Xiao Y, Zhao Z, Ye S, Rao H, Ting H, Bian Z, Xiao L, Huang C, et al. An ammonia modified PEDOT: PSS for interfacial engineering in inverted planar perovskite solar cells. ORGANIC ELECTRONICS. 2017;46:22-27.
Sun W, Li Y, Xiao Y, Zhao Z, Ye S, Rao H, Ting H, Bian Z, Xiao L, Huang C, et al. An ammonia modified PEDOT: PSS for interfacial engineering in inverted planar perovskite solar cells. ORGANIC ELECTRONICS. 2017;46:22-27.Abstract
Poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS) is one of the most widely used hole transport layers (HTL) in inverted perovskite solar cells (PSCs) due to its simple solution-processed ability, high transparency, and conductivity. However, PEDOT: PSS-based devices suffer a lower open-circuit voltage (V-oc) than devices with the conventional structure. To address this issue, we fabricated ammonia-modified PEDOT: PSS films by simply doping PEDOT: PSS solution with different ratio of ammonia. The acidity of PEDOT: PSS can be neutralized by the doped ammonia, which inhibits the ion-exchange reaction between PSS-H and CH3NH3I, thus retarding the reduction of the work function for PEDOT: PSS to some extent. As a result, a superior power conversion efficiency (PCE) of 15.5% was obtained for the device based on the ammonia-doped PEDOT: PSS HTL than that of the pristine PEDOT: PSS-based device. We ascribe the PCE enhancement to the increased Voc and fill factor (FF), which is attributed not only to the better energy-level alignment between the ammonia-modified PEDOT: PSS film and perovskite layer but also to the increased grain size and crystallinity of perovskite film. (C) 2017 Published by Elsevier B.V.
Liu YJ, Lu YQ, Yang XS, Zheng XL, Wen SH, Wang F, Vidal X, Zhao JB, Liu DM, Zhou ZG, et al. Amplified stimulated emission in upconversion nanoparticles for super-resolution nanoscopy. Nature [Internet]. 2017;543(7644):229-233. 访问链接Abstract
Lanthanide-doped glasses and crystals are attractive for laser applications because the metastable energy levels of the trivalent lanthanide ions facilitate the establishment of population inversion and amplified stimulated emission at relatively low pump power(1-3). At the nanometre scale, lanthanide-doped upconversion nanoparticles (UCNPs) can now be made with precisely controlled phase, dimension and doping level(4,5). When excited in the near-infrared, these UCNPs emit stable, bright visible luminescence at a variety of selectable wavelengths(6-9), with single-nanoparticle sensitivity(10-13), which makes them suitable for advanced luminescence microscopy applications. Here we show that UCNPs doped with high concentrations of thulium ions (Tm3+), excited at a wavelength of 980 nanometres, can readily establish a population inversion on their intermediate metastable H-3(4) level: the reduced inter-emitter distance at high Tm3+ doping concentration leads to intense cross-relaxation, inducing a photon-avalanche-like effect that rapidly populates the metastable H-3(4) level, resulting in population inversion relative to the H-3(6) ground level within a single nanoparticle. As a result, illumination by a laser at 808 nanometres, matching the upconversion band of the H-3(4)-> H-3(6) transition, can trigger amplified stimulated emission to discharge the H-3(4) intermediate level, so that the upconversion pathway to generate blue luminescence can be optically inhibited. We harness these properties to realize low-power super-resolution stimulated emission depletion (STED) microscopy and achieve nanometre-scale optical resolution (nanoscopy), imaging single UCNPs; the resolution is 28 nanometres, that is, 1/36th of the wavelength. These engineered nanocrystals offer saturation intensity two orders of magnitude lower than those of fluorescent probes currently employed in stimulated emission depletion microscopy, suggesting a new way of alleviating the square-root law that typically limits the resolution that can be practically achieved by such techniques.
Tao L, Zhu K, Zhu JG, Xu XH, Lin C, Ma WJ, Lu HY, Zhao YY, Lu YR, Chen JE, et al. An analytical reconstruction model of the spread-out Bragg peak using laser-accelerated proton beams. Physics in Medicine and Biology [Internet]. 2017;62:5200-5212. 访问链接Abstract
With the development of laser technology, laser-driven proton acceleration provides a new method for proton tumor therapy. However, it has not been applied in practice because of the wide and decreasing energy spectrum of laser-accelerated proton beams. In this paper, we propose an analytical model to reconstruct the spread-out Bragg peak (SOBP) using laser-accelerated proton beams. Firstly, we present a modified weighting formula for protons of different energies. Secondly, a theoretical model for the reconstruction of SOBPs with laser-accelerated proton beams has been built. It can quickly calculate the number of laser shots needed for each energy interval of the laser-accelerated protons. Finally, we show the 2D reconstruction results of SOBPs for laser-accelerated proton beams and the ideal situation. The final results show that our analytical model can give an SOBP reconstruction scheme that can be used for actual tumor therapy.
Yang Y, Zhang P. Analyzing Patterns of Contribution to User-generated Tag Hierarchies Based on Core User Types. ASIST '17 Proceedings. 2017.
Antagonistic effect of humic acid and naphthalene on biochar colloid transport in saturated porous media
Yang W, Wang Y, Shang J, Liu K, Sharma P, Liu J, Li B. Antagonistic effect of humic acid and naphthalene on biochar colloid transport in saturated porous media. Chemosphere. 2017.
Bateman AP, Gong Z, Harder TH, de Sá SS, Wang B, Castillo P, China S, Liu Y, O'Brien RE, Palm BB, et al. Anthropogenic influences on the physical state of submicron particulate matter over a tropical forest. Atmospheric Chemistry and Physics [Internet]. 2017;17(3):1759–1773. Link
XIAO L. The Application of Knowledge Management in Organizational Restructuring of Academic Libraries: A Case Study of Peking University Library. IFLA open session, in IFLA World Library and Information Congress 2017 (83rd IFLA General Conference and Assembly). Wrocław, Poland : IFLA Library; 2017. 访问链接
Pan F, Yu Y, Xu A, Xia D, Sun Y, Cai Z, Liu W, Fu J. Application of magnetic OMS-2 in sequencing batch reactor for treating dye wastewater as a modulator of microbial community. Journal of Hazardous Materials. 2017;340:36-46.
Shi W, Nolte CG, Loughlin DH, Ou Y, Smith SJ. Assessing the Energy and Emissions Implications of Alternative Population Scenarios Using a State-Level Integrated Assessment Model. AGU Fall Meeting Abstracts. 2017;2017:GC13B-0786.
Rossi R, Yang W, Setti L, Logan BE. Assessment of a metal–organic framework catalyst in air cathode microbial fuel cells over time with different buffers and solutions. Bioresource technology. 2017;233:399-405.
Rossi R, Yang W, Setti L, Logan BE. Assessment of a metal–organic framework catalyst in air cathode microbial fuel cells over time with different buffers and solutions. Bioresource technology. 2017;233:399–405.
Altemose B, Robson MG, Kipen HM, Strickland PO, Meng QY, Gong JC, Huang W, Wang GF, Rich DQ, Zhu T, et al. Association of air pollution sources and aldehydes with biomarkers of blood coagulation, pulmonary inflammation, and systemic oxidative stress. Journal of Exposure Science and Environmental Epidemiology. 2017;27:244-250.Abstract
Using data collected before, during, and after the 2008 Summer Olympic Games in Beijing, this study examines associations between biomarkers of blood coagulation (vWF, sCD62P and sCD40L), pulmonary inflammation (EBC pH, EBC nitrite, and eNO), and systemic oxidative stress (urinary 8-OHdG) with sources of air pollution identified utilizing principal component analysis and with concentrations of three aldehydes of health concern. Associations between the biomarkers and the air pollution source types and aldehydes were examined using a linear mixed effects model, regressing through seven lag days and controlling for ambient temperature, relative humidity, gender, and day of week for the biomarker measurements. The biomarkers for pulmonary inflammation, particularly EBC pH and eNO, were most consistently associated with vehicle and industrial combustion, oil combustion, and vegetative burning. The biomarkers for blood coagulation, particularly vWF and sCD62p, were most consistently associated with oil combustion. Systemic oxidative stress biomarker (8-OHdG) was most consistently associated with vehicle and industrial combustion. The associations of the biomarkers were generally not significant or consistent with secondary formation of pollutants and with the aldehydes. The findings support policies to control anthropogenic pollution sources rather than natural soil or road dust from a cardio-respiratory health standpoint.
Jennings L, Yang F, Otupiri E, Akinlo A, Okunlola M, Hindin M. Association of household savings and expected future means with delivery using a skilled birth attendant in Ghana and Nigeria: a cross-sectional analysis. Maternal and child health journal. 2017;21(1):85-95.
Day DB, Xiang J, Mo J, Li F, Chung M, Gong J, Weschler CJ, Ohman-Strickland PA, Sundell J, Weng W, et al. Association of Ozone Exposure With Cardiorespiratory Pathophysiologic Mechanisms in Healthy Adults. JAMA Intern Med. 2017;177:1344-1353.Abstract
Importance: Exposure to ozone has been associated with cardiovascular mortality, but the underlying biological mechanisms are not yet understood. Objective: To examine the association between ozone exposure and cardiopulmonary pathophysiologic mechanisms. Design, Setting, and Participants: A longitudinal study involving 89 healthy adult participants living on a work campus in Changsha City, China, was conducted from December 1, 2014, to January 31, 2015. This unique quasiexperimental setting allowed for better characterization of air pollutant exposure effects because the participants spent most of their time in controlled indoor environments. Concentrations of indoor and outdoor ozone, along with the copollutants particulate matter, nitrogen dioxide, and sulfur dioxide, were monitored throughout the study period and then combined with time-activity information and filtration conditions of each residence and office to estimate 24-hour and 2-week combined indoor and outdoor mean exposure concentrations. Associations between each exposure measure and outcome measure were analyzed using single-pollutant and 2-pollutant linear mixed models controlling for ambient temperature, secondhand smoke exposure, and personal-level time-varying covariates. Main Outcomes and Measures: Biomarkers indicative of inflammation and oxidative stress, arterial stiffness, blood pressure, thrombotic factors, and spirometry were measured at 4 sessions. Results: Of the 89 participants, 25 (28%) were women and the mean (SD) age was 31.5 (7.6) years. The 24-hour ozone exposure concentrations ranged from 1.4 to 19.4 parts per billion (ppb), corresponding to outdoor concentrations ranging from 4.3 to 47.9 ppb. Within this range, in models controlling for a second copollutant and other potential confounders, a 10-ppb increase in 24-hour ozone was associated with mean increases of 36.3% (95% CI, 29.9%-43.0%) in the level of platelet activation marker soluble P-selectin, 2.8% (95% CI, 0.6%-5.1%) in diastolic blood pressure, 18.1% (95% CI, 4.5%-33.5%) in pulmonary inflammation markers fractional exhaled nitric oxide, and 31.0% (95% CI, 0.2%-71.1%) in exhaled breath condensate nitrite and nitrate as well as a -9.5% (95% CI, -17.7% to -1.4%) decrease in arterial stiffness marker augmentation index. A 10-ppb increase in 2-week ozone was associated with increases of 61.1% (95% CI, 37.8%-88.2%) in soluble P-selectin level and 126.2% (95% CI, 12.1%-356.2%) in exhaled breath condensate nitrite and nitrate level. Other measured biomarkers, including spirometry, showed no significant associations with either 24-hour ozone or 2-week ozone exposures. Conclusions and Relevance: Short-term ozone exposure at levels not associated with lung function changes was associated with platelet activation and blood pressure increases, suggesting a possible mechanism by which ozone may affect cardiovascular health.

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