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إنتاج الطاقة الحيوية والوقود الحيوي من النفايات والكتلة الحيوية
توفر فصول هذا الكتاب أحدث استعراض ومسح للبحوث والتطورات التقنية، فيما يتعلق بالجيلين الثاني والثالث من الوقود الحيوي والطاقة الحيوية، كما تعرض الاتجاهات البحثية الحالية والمستقبلية في نهاية كل فصل ويغطي هذا الكتاب في المقام الأول، التحويل البيولوجي والكيميائي الحيوي لإنتاج الوقود الحيوي والطاقة الحيوية، باعتباره خيارا معلنا ورخيصا لإنتاج الوقود الحيوي والطاقة الحيوية. يعد هذا الكتاب مرجعا قيما، لطلاب المرحلة الجامعية والدراسات العليا والباحثين في الكيمياء والكيمياء الحيوية والبيئة والمجالات الهندسية وصناع القرار والمهنيين الممارسين وغيرهم من المهتمين بمجال الوقود الحيوي والطاقة الحيوية.
Book
Observations of relative humidity effects on aerosol light scattering in the Yangtze River Delta of China
Scattering of solar radiation by aerosol particles is highly dependent on relative humidity (RH) as hygroscopic particles take up water with increasing RH. To achieve a better understanding of the effect of aerosol hygroscopic growth on light scattering properties and radiative forcing, the aerosol scattering coefficients at RH in the range of 40 to ~ 90 % were measured using a humidified nephelometer system in the Yangtze River Delta of China in March 2013. In addition, the aerosol size distribution and chemical composition were measured. During the observation period, the mean and standard deviation (SD) of enhancement factors at RH = 85 % for the scattering coefficient (f(85 %)), backscattering coefficient (fb(85 %)), and hemispheric backscatter fraction (fβ(85 %)) were 1.58 ± 0.12, 1.25 ± 0.07, and 0.79 ± 0.04, respectively, i.e., aerosol scattering coefficient and backscattering coefficient increased by 58 and 25 % as the RH increased from 40 to 85 %. Concurrently, the aerosol hemispheric backscatter fraction decreased by 21 %. The relative amount of organic matter (OM) or inorganics in PM1 was found to be a main factor determining the magnitude of f(RH). The highest values of f(RH) corresponded to the aerosols with a small fraction of OM, and vice versa. The relative amount of NO3− in fine particles was strongly correlated with f(85 %), which suggests that NO3− played a vital role in aerosol hygroscopic growth during this study. The mass fraction of nitrate also had a close relationship to the curvature of the humidograms; higher mass fractions of nitrate were associated with humidograms that had the least curvature. Aerosol hygroscopic growth caused a 47 % increase in the calculated aerosol direct radiative forcing at 85 % RH, compared to the forcing at 40 % RH.
Journal Article
Quantifying atmospheric nitrogen deposition through a nationwide monitoring network across China
A Nationwide Nitrogen Deposition Monitoring Network (NNDMN) containing 43 monitoring sites was established in China to measure gaseous NH3, NO2, and HNO3 and particulate NH4+ and NO3− in air and/or precipitation from 2010 to 2014. Wet/bulk deposition fluxes of Nr species were collected by precipitation gauge method and measured by continuous-flow analyzer; dry deposition fluxes were estimated using airborne concentration measurements and inferential models. Our observations reveal large spatial variations of atmospheric Nr concentrations and dry and wet/bulk Nr deposition. On a national basis, the annual average concentrations (1.3–47.0 μg N m−3) and dry plus wet/bulk deposition fluxes (2.9–83.3 kg N ha−1 yr−1) of inorganic Nr species are ranked by land use as urban > rural > background sites and by regions as north China > southeast China > southwest China > northeast China > northwest China > Tibetan Plateau, reflecting the impact of anthropogenic Nr emission. Average dry and wet/bulk N deposition fluxes were 20.6 ± 11.2 (mean ± standard deviation) and 19.3 ± 9.2 kg N ha−1 yr−1 across China, with reduced N deposition dominating both dry and wet/bulk deposition. Our results suggest atmospheric dry N deposition is equally important to wet/bulk N deposition at the national scale. Therefore, both deposition forms should be included when considering the impacts of N deposition on environment and ecosystem health.
Journal Article
STCF conceptual design report (Volume 1): Physics & detector
The super τ-charm facility (STCF) is an electron−positron collider proposed by the Chinese particle physics community. It is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5 × 10 35 cm −2·s −1 or higher. The STCF will produce a data sample about a factor of 100 larger than that of the present τ-charm factory - the BEPCII, providing a unique platform for exploring the asymmetry of matter-antimatter (charge-parity violation), in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions, as well as searching for exotic hadrons and physics beyond the Standard Model. The STCF project in China is under development with an extensive R&D program. This document presents the physics opportunities at the STCF, describes conceptual designs of the STCF detector system, and discusses future plans for detector R&D and physics case studies.
Journal Article
Direct detection of a break in the teraelectronvolt cosmic-ray spectrum of electrons and positrons
A direct measurement of cosmic-ray electrons and positrons with unprecedentedly high energy resolution reveals a spectral break at about 0.9 teraelectronvolts, confirming the evidence found by previous indirect measurements.
A break in the cosmic-ray spectrum
The spectrum of cosmic-ray electrons and positrons that arrive at Earth potentially contains information about the sources that accelerated them, and may reveal dark-matter annihilation. The spectrum has previously been measured directly up to around 2 teraelectronvolts (TeV), and indirectly up to around 5 TeV from ground-based Cherenkov arrays, which revealed a possible break in the spectrum. The Dark Matter Particle Explorer (DAMPE) Collaboration reports a direct measurement between 25 gigaelectronvolts and 4.6 TeV, which clearly reveals a spectral break at around 0.9 TeV.
High-energy cosmic-ray electrons and positrons (CREs), which lose energy quickly during their propagation, provide a probe of Galactic high-energy processes
1
,
2
,
3
,
4
,
5
,
6
,
7
and may enable the observation of phenomena such as dark-matter particle annihilation or decay
8
,
9
,
10
. The CRE spectrum has been measured directly up to approximately 2 teraelectronvolts in previous balloon- or space-borne experiments
11
,
12
,
13
,
14
,
15
,
16
, and indirectly up to approximately 5 teraelectronvolts using ground-based Cherenkov γ-ray telescope arrays
17
,
18
. Evidence for a spectral break in the teraelectronvolt energy range has been provided by indirect measurements
17
,
18
, although the results were qualified by sizeable systematic uncertainties. Here we report a direct measurement of CREs in the energy range 25 gigaelectronvolts to 4.6 teraelectronvolts by the Dark Matter Particle Explorer (DAMPE)
19
with unprecedentedly high energy resolution and low background. The largest part of the spectrum can be well fitted by a ‘smoothly broken power-law’ model rather than a single power-law model. The direct detection of a spectral break at about 0.9 teraelectronvolts confirms the evidence found by previous indirect measurements
17
,
18
, clarifies the behaviour of the CRE spectrum at energies above 1 teraelectronvolt and sheds light on the physical origin of the sub-teraelectronvolt CREs.
Journal Article
Atmospheric aerosol compositions in China: spatial/temporal variability, chemical signature, regional haze distribution and comparisons with global aerosols
From 2006 to 2007, the daily concentrations of major inorganic water-soluble constituents, mineral aerosol, organic carbon (OC) and elemental carbon (EC) in ambient PM10 samples were investigated from 16 urban, rural and remote sites in various regions of China, and were compared with global aerosol measurements. A large difference between urban and rural chemical species was found, normally with 1.5 to 2.5 factors higher in urban than in rural sites. Optically-scattering aerosols, such as sulfate (~16%), OC (~15%), nitrate (~7%), ammonium (~5%) and mineral aerosol (~35%) in most circumstance, are majorities of the total aerosols, indicating a dominant scattering feature of aerosols in China. Of the total OC, ~55%–60% can be attributed to the formation of the secondary organic carbon (SOC). The absorbing aerosol EC only accounts for ~3.5% of the total PM10. Seasonally, maximum concentrations of most aerosol species were found in winter while mineral aerosol peaks in spring. In addition to the regular seasonal maximum, secondary peaks were found for sulfate and ammonium in summer and for OC and EC in May and June. This can be considered as a typical seasonal pattern in various aerosol components in China. Aerosol acidity was normally neutral in most of urban areas, but becomes some acidic in rural areas. Based on the surface visibility observations from 681 meteorological stations in China between 1957 and 2005, four major haze areas are identified with similar visibility changes, namely, (1) Hua Bei Plain in N. China, and the Guanzhong Plain; (2) E. China with the main body in the Yangtze River Delta area; (3) S. China with most areas of Guangdong and the Pearl River Delta area; (4) The Si Chuan Basin in S.W. China. The degradation of visibility in these areas is linked with the emission changes and high PM concentrations. Such quantitative chemical characterization of aerosols is essential in assessing their role in atmospheric chemistry and weather-climate effects, and in validating atmospheric models.
Journal Article
Environmental impacts of nitrogen emissions in China and the role of policies in emission reduction
Atmospheric reactive nitrogen (N
r
) has been a cause of serious environmental pollution in China. Historically, China used too little N
r
in its agriculture to feed its population. However, with the rapid increase in N fertilizer use for food production and fossil fuel consumption for energy supply over the last four decades, increasing gaseous N
r
species (e.g. NH
3
and NO
x
) have been emitted to the atmosphere and then deposited as wet and dry deposition, with adverse impacts on air, water and soil quality as well as plant biodiversity and human health. This paper reviews the issues associated with this in a holistic way. The emissions, deposition, impacts, actions and regulations for the mitigation of atmospheric N
r
are discussed systematically. Both NH
3
and NO
x
make major contributions to environmental pollution but especially to the formation of secondary fine particulate matter (PM
2.5
), which impacts human health and light scattering (haze). In addition, atmospheric deposition of NH
3
and NO
x
causes adverse impacts on terrestrial and aquatic ecosystems due to acidification and eutrophication. Regulations and practices introduced by China that meet the urgent need to reduce N
r
emissions are explained and resulting effects on emissions are discussed. Recommendations for improving future N management for achieving ‘win-win’ outcomes for Chinese agricultural production and food supply, and human and environmental health, are described.
This article is part of a discussion meeting issue ‘Air quality, past present and future’.
Journal Article
Test of local realism via entangled ΛΛ¯ system
The non-locality of quantum correlations is a fundamental feature of quantum theory. The Bell inequality serves as a benchmark for distinguishing between predictions made by quantum theory and local hidden variable theory (LHVT). Recent advancements in photon-entanglement experiments have addressed potential loopholes and have observed significant violations of variants of Bell inequality. However, examples of Bell inequalities violation in high energy physics are scarce. In this study, we utilize (10.087 ± 0.044) × 10
9
J
/
ψ
events collected with the BES-III detector at the BEPCII collider, performing non-local correlation tests using the entangled hyperon pairs. The massive-entangled
Λ
Λ
¯
systems are formed and decay through strong and weak interactions, respectively. Through measurements of the angular distribution of
p
p
¯
in
J
/
ψ
→
γ
η
c
and subsequent
η
c
→
Λ
(
p
π
−
)
Λ
¯
(
p
¯
π
+
)
cascade decays, a significant violation of LHVT predictions is observed. The exclusion of LHVT is found to be statistically significant at a level exceeding 5.2
σ
in the testing of three Bell-like inequalities.
While Bell inequalities have been violated several times—mostly in photonic systems—their violations within particle physics experiments are less explored. Here, the BESIII Collaboration showcases Bell-violating nonlocal correlations between entangled hyperon pairs.
Journal Article
Role of miR-143 targeting KRAS in colorectal tumorigenesis
Dysregulated expression of microRNAs (miRNAs) is associated with a variety of diseases, including colorectal cancer. By comparing more than 200 miRNAs in 13 pairs of matched colorectal cancer and normal adjacent tissue samples through qRT-PCR and microarray analysis, we found a widespread disruption of miRNA expression during colorectal tumorigenesis. In particular, among a panel of presumed targets generated by
in silico
analysis that may interact with these aberrantly expressed miRNAs, KRAS oncogene has been further experimentally validated as the target of miR-143. First, an inverse correlation between KRAS protein and miR-143
in vivo
was found. Second, KRAS expression in Lovo cells was significantly abolished by treatment with miR-143 mimic, whereas miR-143 inhibitor increased KRAS protein level. Third, luciferase reporter assay confirmed that miR-143 directly recognize the 3′-untranslated region of KRAS transcripts. Four, Lovo cells treated with miR-143 inhibitor showed a stimulated cell proliferation, whereas miR-143 overexpression had an opposite effect. Finally, inhibition of KRAS expression by miR-143 inhibits constitutive phosphorylation of ERK1/2. Taken together, the present study provides the first evidences that miR-143 is significant in suppressing colorectal cancer cell growth through inhibition of KRAS translation.
Journal Article