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Turbocharger turbine blades suffer from periodic vibration and flow induced excitation. The blade vibration signal is a typical non-stationary and sometimes nonlinear signal that is often encountered in turbomachinery research and development. An example of such signal is the pulsating pressure and strain signals measured during engine ramp to find the maximum resonance strain or during engine transient mode in applications. As the pulsation signals can come from different disturbance sources, detecting the weak useful signals under a noise background can be difficult. For this type of signals, a novel method based on optimal parameters of Ensemble Empirical Mode Decomposition (EEMD) and Teager Energy Operator (TEO) is proposed. First, an optimization method was designed for adaptive determining appropriate EEMD parameters for the measured vibration signal, so that the significant feature components can be extracted from the pulsating signals. Then Correlation Kurtosis (CK) is employed to select the sensitive Intrinsic Mode Functions (IMFs). In the end, TEO algorithm is applied to the selected sensitive IMF to identify the characteristic frequencies. A case of measured sound signal and strain signal from a turbocharger turbine blade was studied to demonstrate the capabilities of the proposed method
Balancing sustained economic growth with energy security and environmental and climate change constraints is a common but difficult challenge. China, as the largest energy consumer in the world – 90% of which is fossil fuel-based – faces the enormous task of transforming its energy mix to low-emissions. CO₂ has been successfully injected for the purposes of both carbon capture and storage (CCS) and enhanced oil recovery (EOR). This study employs life cycle assessment to quantify the CO₂ emissions from the CCS-EOR system to analyze net CO₂ emissions. This system includes carbon capture, transportation, EOR, downstream, and consumption. Our model analyzes life cycle CO₂ emissions from plants of integrated gasification combined cycle (IGCC) with CCS, pulverized coal plants (PC) with CCS, and oxy-fuel plants with CCS while we use technologies of fractionation, refrigeration, Ryan-Holmes, and membrance in the process of EOR. Total CO₂ emissions are 114.69-121.50 Mt CO₂e, 222.95-236.19 Mt CO₂e, and 49.09-51.96 Mt CO₂e from IGCC, PC, and oxy-fuel plants, respectively, based on IGCC with 426 MW, PC with 600 MW, and oxy-fuel with 200 MW in China. Emissions from the combustion of refined petroleum fuel is the most of total emissions – from 66.21% to 71.35%, emissions from EOR are 14.27-19.32%, emissions from downstream are 8.47-9.13%, emissions from capture are 4.12-5.09%, and emissions from transportation are 0.47-1.61%. Based on these results, CCS-EOR (where CO₂ is sourced from IGCC, PC and oxy-fuel plants) provides one potential means for producing electricity and oil to meet growing energy demand and reducing CO₂ emissions to abate global warming.
Resource endowment and resource carrying capacity (RCC) are the most important cornerstones of regional sustainable development. By applying a newly established RCC method, namely, the relative resources carrying capacity (RRCC) method, we evaluated the RCC in the Tarim River basin (TRB) in arid China in Xinjiang during 2000-2011. Research results show that the relative resources carrying capacity can be effectively served as indicators of regional resources sustainable development status. Taking Xinjiang as the reference region, the TRB can be characterized as an area with an overloaded population and surplus economy during the whole research period, where land resources are relative advantage resources carrying the regional population growth and economic development and water resources are relative disadvantage resources restricting rapid regional development. Taking TRB as the reference region, 42 counties and cities in TRB performed significant temporal and spatial disparities according to the RRCC based on population and economic perspectives. Based on the spatial-temporal evolution of RRCC, 42 counties and cities in TRB were classified into four matching modes (A, B, C, and D). The spatial-temporal evolution characteristics and mechanisms about the 42 prefectures and cities were examined, and the suitable development strategies for every different mode were recommended.
In order to ensure the safety and reliability of the horizontal brace of semi-submersible platform (SEMI) which functions as the supporting structure in SEMI, this article presents an elastic-plastic method to analyze the variations of the crack tip opening displacement, elastic zone and plastic zone of the cracked section of the horizontal brace under beam wave. The brace of the SEMI was assumed to be located a circumferential through crack at its boundary in this article. In addition, the cracked section of the brace has been divided into crack zone, tensile plastic zone, elastic zone and compressive plastic zone in the presented theoretical model. Moreover, the closed form of the solution has been found in this article which is especially suitable solving complicated problems in practical engineering application. Also, a typical new-generation SEMI that is in practical use was selected to analyze the variation tendency of the cracked brace’s parameters using the proposed model which could give good suggestion to semi-submersible platform designers and managers
Nicotine is the major alkaloid in tobacco and its biosynthesis is regulated by a variety of factors. Topping, as an important agronomic factor, can induce the nicotine biosynthesis increase. Some key nicotine biosynthesisrelated genes and the framework of nicotine biosynthesis pathway have been well studied, but the details of nicotine biosynthesis pathway are not well understood now. To investigate the genes expressed after tobacco topping, we constructed a suppression subtractive hybridization library using cDNA from control tobacco plants as driver and those from topped tobacco plants as tester. The insert size of positive clones was 200–1,000 bp confirmed by PCR. After differential screening, 560 significantly differently expressed clones among 1,950 positive clones were acquired, sequenced and 273 high quality expressed sequence tags (ESTs) were acquired. The results of nucleotide blast homological analysis indicated that these ESTs mainly involved in alkaloid biosynthesis (4%), plant hormone metabolism (3%), signaling/transcription (18%), stress/ defense (32%), protein metabolism (9%), carbon metabolism (6%), other metabolism (15%) and function unknown (13%). The expression of selected genes was analyzed by reverse transcription polymerase chain reaction and RNA gel blot hybridization, and the result indicated that their transcription amount increased after tobacco topping. NtNAC-R1was in silico cloned, and the expression level of NtNAC-R1 increased at 12 and 24 h in tobacco roots after topping, which indicated that NtNAC-R1 may play an important role in the signal transduction after tobacco topping. In addition to many previously reported nicotine biosynthesis-related genes, some new genes, such as transcription factors related to nicotine biosynthesis/regulation and the members of plant hormone pathway, were discovered in our library. The results contribute new data to the list of possible candidate genes involved in nicotine biosynthesis and regulation.
This study evaluated the effects of addition of lucerne extract (LE), Artemisiae annuae extract (AAE), and mixed herbal medicine (MHM) into different goat diets on in vitro rumen fermentation and methane production. In addition to the negative control (NC), addition of monensin (MO) served as the positive control (PC). Four ruminally cannulated Nanjiang Yellow goats (45 ± 2 kg liveweight) were used as donors of ruminal fluid. The results showed: 1. compared with NC, addition of all the additives into the mixed grass diet increased propionate concentration (P<0.05). Protozoa numbers and methane production were reduced by addition of all the additives (P<0.05); 2. compared with NC, LE and AAE in the lucerne diet increased propionate concentration (P<0.05). All the additives reduced protozoa numbers (P<0.05). Methane production was decreased by addition of LE compared with NC and PC (P<0.05); 3. addition of LE into the mixed grass-concentrate diet resulted in an increase of the propionate concentration compared with NC and PC (P<0.05). Protozoa numbers were reduced by addition of LE and AAE compared with NC (P<0.05). Methane production was decreased by addition of AAE compared with NC and PC (P<0.05); 4. compared with NC, addition of AAE and MHM into the lucerne-concentrate diet resulted in an increase of propionate concentration (P<0.05). Protozoa numbers were reduced by addition of all the additives (P<0.05). Methane production was decreased by addition of AAE and MHM (P<0.05). In conclusion, addition of LE, AAE and MHM into different diets reduced methane production, increased propionate concentration and decreased protozoa numbers to a certain extent, and the inhibitory effects of the phytogenic products on methane production are more remarkable in the mixed-grass diet. The phytogenic products appear to be promising alternatives to MO in altering in vitro rumen fermentation and reducing methane production in goats.
To achieve emission reduction targets in China, it is necessary to analyze the factors driving energyrelated carbon emissions from a regional perspective. We used extended STIRPAT model (stochastic impacts by regression on population, affluence, and technology) based on the classical IPAT identity (where I = impact representing carbon emissions, P = population, A = affluence, and T = emission intensity) to determine the main factors driving energy-related carbon emissions in Xinjiang from 1952 to 2014, an important Chinese energy base in northwestern China. Total carbon emissions in Xinjiang were found to increase from 28.51 × 10⁴ t in 1952 to 9,446.61 × 10⁴ t in 2014, representing a 331.34-fold increase over a period of 63 years. Results show that the impacts and influences of various factors on carbon emissions varied among three stages of development: “Before Reform and Opening up” (1952-1977), “After Reform and Opening up” (1978-2000), and “Western Development” (2001-2014). In the first stage, emission intensity and population size were the dominant contributors to increments in carbon emissions, while the energy consumption structure played an important role in curbing carbon emissions. In the second stage, economic growth and population size were the dominant contributors to increments in carbon emissions, while emission intensity had a significant negative effect on carbon emissions. In the third stage, fixed asset investment and economic growth were the dominant contributors to increments in carbon emissions, while emission intensity had a significant negative effect on carbon emissions.
Understanding drivers for energy consumption is important for economic and environmentally sustainable development. To explore this issue, the SDA (structural decomposition analysis) method based on input-output theory was used to analyze the influencing mechanism of energy consumption in one of the top energy consumers, Guangdong Province in China, during 2002 to 2012. We divided the process into 2 stages: before and after the global financial crisis. The main conclusions are as follows: 1) Economic activity and population size are the main driving factors for the increase in energy consumption, while energy consumption intensity is the main factor restraining the increment, and the effects of final demand structure on energy consumption transformed from positive before the global financial crisis to negative after the global financial crisis. 2) Analysis of allocation of energy consumption changes caused by final demands shows that international and domestic trade had significant effects on changes in energy consumption. Although energy consumption embodied in international exports decreased after the global financial crisis, it is still the most significant important driver for the increments. Guangdong is a net exporter of embodied energy through international trade, while its energy-saving achievement is partly due to embodied energy transfers via China’s domestic trade.
In our previous research, we showed that the cyclin-dependent kinase regulatory subunit (CKS2) in maize (Zea mays L.) was induced by water deficit and cold stress. To elucidate its expression patterns under adversity, we isolated and characterized its promoter (PZmCKS2). A series of PZmCKS2-deletion derivatives, P0–P3, from the translation start code (-1,455, -999, -367, and -3 bp) was fused to the β-glucuronidase (GUS) reporter gene, and each deletion construct was analyzed by Agrobacterium-mediated steady transformation into Arabidopsis. Leaves were then subjected to dehydration, cold, abscisic acid (ABA), salicylic acid (SA), and methyl jasmonic acid (MeJA). Sequence analysis showed that several stressrelated cis-acting elements (MBS, CE3, TGA element, and ABRE) were located within the promoter. Deletion analysis of the promoter, PZmCKS2, suggested that the -999 bp promoter region was required for the highest basal expression of GUS, and the -367 bp sequence was the minimal promoter for ZmCKS2 activation by low temperature, ABA, and MeJA. The cis-acting element ABRE was necessary for promoter activation by exogenous ABA.
Atmospheric sulfur dioxide (SO₂) is a major air pollutant and has the most negative effect on atmospheric chemistry. In this study, measurements of SO₂ column concentration obtained from an ozone monitoring instrument (OMI) are used to investigate the temporal and spatial dynamics of SO₂. Temporal and spatial distributions of SO₂ concentrations obtained from OMI over the Beijing-Tianjin-Hebei (Jing-Jin-Ji) region from 2007 to 2016 are presented, and annual changes and trends in the seasonal cycle are shown. The annual variations of SO₂ concentration are found to have decreased 47.6% from 2007 to 2016, and the SO₂ concentration shows a high correlation with SO₂ emissions. SO₂ shows significant cyclical seasonal characteristics over Jing-Jin-Ji, with maximum values in winter and minimum in summer; both temperature and precipitation are negatively correlated with SO₂ concentrations in seasonal variations. In addition, the spatial distribution is unbalanced, and Shijiazhuang-Xingtai-Handan is found to be in highly polluted areas, which may be related to energy consumption. The overall trends in the average annual value of SO₂ in the 13 sites appear to have decreased since 2007, and SO₂ concentrations in the Shijiazhuang-Xingtai-Handan region decreased by 55% during the past decade, so the Chinese government has made great efforts in pollution reduction, and has achieved remarkable results.
C-repeat binding factor (CBF) signaling pathway is involved in cold acclimation responsive to low temperature and some other stresses. CBF transcription factor family is the key component of this pathway. In this study, eight CBF-like genes, BrCBF1, BrCBF2, BrCBF3, BrCBF4, BrCBF5, and BrCBF6A/B/C were isolated from non-heading Chinese cabbage (Brassica campestris ssp. chinensis L. Makino, NHCC). The deduced CBF proteins shared high similarity with their Arabidopsis orthologs and localized to the nucleus. Furthermore, quantitative realtime PCR (qPCR) analysis showed that BrCBF1~3 were induced by cold (4 C) but not drought or abscisic acid (ABA), indicating that they are involved in an ABA-independent pathway; however, BrCBF4~6 were regulated by both drought and ABA, suggesting that they were involved in an ABA-dependent pathway. Nevertheless, unlike Arabidopsis, BrCBF4~6 showed response to both cold and ABA, indicates ABA-independent and ABA-dependent parts of CBF pathway in NHCC might not be completely separate, and these genes may act as the connection points in the network. BrCBFs were also accumulated in response to salicylic acid (SA), methyljasmonate (MeJA), and ethylene (ET), indicating that BrCBF genes might participate in the response to biotic stresses. Taken together, eight CBF genes were isolated from NHCC which compose a functional CBF signaling pathway by participating in response to multiple stresses and performing roles from Arabidopsis to some extent.
Expression of single-chain variable fragment (scFv) antibodies on the surface of bacteriophage is widely used to prepare antibodies with pre-defined specificities. A phage antibody library containing the gene for scFv antibody against Hepatitis C virus core protein was panned with core protein immobilized on microtiter plate wells. After five rounds of panning 60 phage clones specific to core protein were obtained and one selected clone was sequenced. It was found that the specifically detected antigen consists of 774bp and is capable of encoding 257 amino acids in the patients but not in healthy persons.
Key message: HSF family transcription factors were analyzed in genome of Chinese cabbage. Chromosomal locations showed that duplication might result in expansion. Response to abiotic stresses was elucidated in Chinese cabbage varieties. Abstract: The major heat shock factors regulating the heat stress response are heat shock transcription factors (HSFs), which interact with heat shock elements. In this study, Chinese cabbage (Brassica rapa L. ssp. pekinensis) HSFs were comprehensively analyzed. A total of 52 HSF family genes were identified for phylogenetic relationships and motif analysis based on the genome sequence of Chinese cabbage. All HSFs were divided into classes A, B, and C. The chromosomal locations and gene duplications of these HSFs were also presented. Nine potential duplication events were found in Chinese cabbage chromosomes. Expression of three HSF genes in two varieties of Chinese cabbage using quantitative real-time PCR revealed that BraHSF039 and BraHSF043 were up-regulated under temperature and salt stresses treatments, and only BraHSF043 gene was also down-regulated under salt stress in ‘Lubaisanhao’. BraHSF001 gene was down-regulated in the ‘Lubaisanhao’ variety under heat and cold stresses, under drought stress in ‘Qingdao 87-114’. These results can serve as a foundation for further studies on HSFs in Brassica.
Evaluating resources and environmental carrying capacity (RECC) plays an important role in sustainable regional development. Using the urban agglomerations of Beijing, Tianjin, and Hebei Province as examples, in this paper we utilize remote sensing (RS) and geographic information system (GIS) techniques to study RECC. Based on data obtained from statistical information and RS technology, we selected 22 indicators with which to construct an RECC evaluation scheme. Then we conducted a mean-variance analysis to determine the weight of each indicator. Finally, we calculated the RECC of each city in the study area and statistically analyzed the main factors influencing RECC. Our results indicate that: • The environment carries the most weight in RECC assessments, followed by resources, economic, and infrastructure • In the study area, the RECC ranking is as follows: Beijing, Tianjin, Chengde, Langfang, Qinhuangdao, Cangzhou, Shijiazhuang, Tangshan, Baoding, Zhangjiakou, Hengshui, Handan, Xingtai • Geographically, the eastern and central regions have higher RECC than the southern and northeast regions • A region’s per capita fiscal income is the most important factor affecting its RECC
The polymorphic markers of nuclear SSR (simple sequence repeat), SNP (single nucleotide polymorphism)/ InDel (insertion–deletion length polymorphism), and cpSSR (chloroplast SSR) were used to evaluate the genetic diversity of 52 trifoliate oranges and their relatives. The two genomic DNA-based markers produced high values of PIC (polymorphic information content) at 0.45 for SNP/InDel and 0.32 for nuclear SSR, indicating that there is a large diversity of genetic variationvwithin the trifoliate oranges. Three UPGMA (unweighted pair-group method with arithmetic means) dendrograms were generated based on the results of three marker systems. At 0.76 of coefficient, all of Poncirus accessions were clustered into one group, except the 74-1 Early Poncirus, one of the three precocious trifoliate oranges, which was placed separately into another group by nuclear SSR. At a higher coefficient, the trifoliate oranges were discriminated into 4, 6 and 6 groups by nuclear SSR (0.86), SNP/InDel (0.95), and cpSSR (0.95), respectively. The results revealed that three precocious trifoliate oranges were originated from different sources. Hubei Early Poncirus and Beibei Early Poncirus were the asexual mutants of different trifoliate oranges, and 74-1 was probably a sexual hybrid. The present study also indicated that ‘Zhiwenzhou,’ a diploid chimera of trifoliate orange and Satsuma is more closely related to Satsuma rather than to trifoliate orange, which is in concordance with the results of morphological observation.
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