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排序方式: 共有574条查询结果,搜索用时 15 毫秒
1.
Sumi Kanij Rukshana Kim Soo Cheol Howlader Jewel Sharker Md Rajib Choi Kap Seong Choi Sang Ki Park Jong-In Nou Ill-Sup Kho Kang Hee 《Ocean Science Journal》2019,54(3):363-374
Ocean Science Journal - A carbonic anhydrase VII gene, encoding 277 amino acids, was identified in the intestinal tissue of pufferfish (Takifugu rubripes). The translated protein with an 833-bp... 相似文献
2.
Sheng Hua Tan Shi Wei Wong Du Jia Chin Min Lee Lee Ying Hui Ong Siaw Yah Chong Azman Kassim 《Environmental Earth Sciences》2018,77(16):589
Rainfall-induced landslide is a common geohazard in tropical and humid regions. Capillary barrier system (CBS) is a popular and widely studied mitigating measure for rainfall-induced landslides. However, several previous studies have shown that the performance of the conventional CBS under intense rainfalls has not been particularly convincing. This paper aims to explore the feasibility and effectiveness of a newly proposed system, known as “biomediated capillary barrier system” (B-CBS) in minimizing water infiltration into soil. A one-dimensional soil column was used to investigate the infiltration characteristics of the proposed system. The results showed that the B-CBS of biomediated residual soil overlying original residual soil (Test IV) could effectively control the infiltration into soil by taking advantage of the less-permeable biomediated soil cover. The B-CBS of biomediated residual soil overlying gravelly sand (Test V) and the three-layered B-CBS of fine sand overlying gravelly sand and biomediated residual soil (Test VI) showed the best performance in terms of minimizing the water infiltration. A suction of about 5 kPa still remained in the soil column after 60 min of infiltration from the ponded water on the soil surface. 相似文献
3.
D. T. Tan S. K. Chin P. E. Poh Y. H. Lee 《International Journal of Environmental Science and Technology》2018,15(6):1211-1222
The generation of huge amount of liquid waste known as palm oil mill effluent is a major problem in oil palm industry. Meanwhile, anaerobic biodegradation of such organic effluent at thermophilic condition is a promising treatment technology due to its high efficiency. However, storage and transportation of thermophilic mixed culture sludge are challenging due to constant biogas generation and heating requirement. Hence, drying of thermophilic sludge was conducted to obtain dormant thermophiles and thus enables easier handling. In this study, thermophilic sludge was dried using heat pump at 22 and 32 °C as well as hot air oven at 40, 50, 60, and 70 °C. Subsequently, quality of dried sludge was examined based on most probable number enumeration, chemical oxygen demand, and methane yield. Average drying rate was found to increase from 3.21 to 17.84 g H2O/m2 min as drying temperatures increases while average moisture diffusivity values ranges from 5.07 × 10?9 to 4.34 × 10?8 m2/s. Oven drying of thermophilic mixed culture resulted in highest chemical oxygen demand removal and lowest log reduction of anaerobes at 53.41% and 2.16, respectively, while heat pump drying resulted in the highest methane yield and lowest log reduction of methanogens at 53.4 ml CH4/g COD and 2.09, respectively. To conclude, heat pump at 22 °C was most suitable drying technique for thermophilic mixed culture as the original methane-producing capability was largely retained after drying, at a slightly lower yet still comparable chemical oxygen demand removal when palm oil mill effluent was treated with the rehydrated culture. 相似文献
4.
Kyoung-nam Jo Kyung Sik Woo Hyoun Soo Lim Hai Cheng R. Lawrence Edwards Yongjin Wang Xiuyang Jiang Ryeon Kim Jae Il Lee Ho Il Yoon Kyu-Cheul Yoo 《Quaternary Science Reviews》2011,30(9-10):1218-1231
Textural and stable isotopic records from the absolute-dated stalagmite of the Daeya Cave (DY-1) provide new insights into the climatic evolution of the Korean Peninsula during the Holocene and Eemian climatic optima. The stalagmite yielded ages of 8572 ± 227 to 5907 ± 158 and 1,23,456 ± 535 to 1,19,837 ± 1089 years, which coincide with the Holocene and Eemian climatic optima, respectively. The stalagmite’s δ13C record closely resembles previously reported Chinese speleothem δ18O data. Thus it can be suggested that textural and geochemical results of the DY-1 reflect East Asian monsoon intensity, which is forced by summer insolation patterns in the northern hemisphere. Lighter carbon isotopic compositions, well-developed fibrous calcite crystals, and their relatively faster growth rate in the stalagmite sample are interpreted to reflect the warmest and wettest climate conditions of the Holocene and Eemian interglacials. Both climatic optima took place when insolation was decreasing from its maximum level, temperature in Greenland was highest, and sea level approached its maximum level. These climatic optima also coincide with decreasing Antarctic temperatures. Compared the DY-1 data to other proxies, it is suggested that the Holocene and Eemian climatic optima developed through a balance among boreal insolation, monsoon intensity, and sea level (also continental ice volume), which are the main climatic forcing factors in the northern hemisphere. These trends also follow the bi-polar seesaw mechanism as previously described. 相似文献
5.
6.
The soil microbiome that plays important ecological roles in mountains and forests is influenced by anthropogenic and natural causes. Human activity, particularly harvesting or thinning, affects the soil microbiome in forests by altering environmental conditions, such as vegetation, microclimate, and soil physicochemical properties. The purpose of this study was to investigate the effects on forest thinning on the diversity and composition of the soil bacterial community. From next-generation sequencing results of the 16S rRNA gene, we examined differences in soil bacterial diversity and community composition before and after thinning at Mt. Janggunbong, South Korea. We identified 40 phyla, 103 classes, 192 orders, 412 families, 947 genera, and 3,145 species from the soil samples. Acidobacteria and Proteobacteria were the most dominant bacterial phyla in the forest soil of Mt. Janggunbong. Soil bacterial diversity measures (richness, Shannon diversity index, and evenness) at the phylum level increased after thinning, whereas species-level taxonomic richness decreased after thinning. Thinning provided new opportunities for bacterial species in Chloroflexi, Verrucomicrobia, Nitrospirae, and other nondominant bacterial taxa, especially for those not found in Mt. Janggunbong before thinning, to settle and adapt to the changing environment. Our results suggested that thinning affected the diversity and composition of soil bacterial communities in forests and mountains. 相似文献
7.
Fredolin T. Tangang Changsui Xia Fangli Qiao Liew Juneng Feng Shan 《Ocean Dynamics》2011,61(9):1317-1328
A wave–tide–circulation coupled model based on Princeton Ocean Model is established to study the seasonal circulation in the
Malay Peninsula Eastern Continental Shelf region. The model successfully reconstructs the observed seasonal variation of the
circulation in the region, as well as the main currents. The simulated tidal harmonic constants, sea surface temperature,
and sea surface height anomaly agree with the observations well. The model results show that the upper-layer circulation in
the region is mainly controlled by the monsoon winds, while there are two transitions in spring and fall. An anti-cyclonic
eddy is present off the Peninsular Malaysia’s east coast in summer, centered at 5°N and 105.5°E, both in the TOPEX/Poseidon
data and in the model. Numerical experiments show that the wind stress curl and bathymetry steering are responsible for its
formation. 相似文献
8.
Evidence for significant clockwise rotations of the Korean Peninsula during Cretaceous 总被引:1,自引:0,他引:1
Youn Soo Lee Hyun-Chul Han Jae Ha Hwang Weon-Seo Kee Bok Chul Kim 《Gondwana Research》2011,20(4):904-918
In an effort to evaluate the Cretaceous magnetostratigraphy for the Korean Peninsula and to establish the tectonic coherence of its various elements, we collected paleomagnetic data from 121 samples from 20 sites within the Chilgok Formation (108.3–109.9 Ma) in the Gyeongsang Basin. Together with previously published data, we evaluate the results from a total of 163 sites in the basin.We combine our age model with results from recent stratigraphic, paleomagnetic and radiometric geochemical studies. In this study, we found that two distinct declination shifts decrease with younging direction, indicating two clockwise rotational events of the Korean Peninsula with respect to the Eurasia continent. The earlier event took place during 130–100 Ma (Phase I, newly termed “Goguryeo Disturbance”) and a later one during 80–50 Ma (Phase III, belonging to “Bulguksa Orogeny”). The mean rotation rate in the interval from 115.2 to 103.8 Ma (Phase I) is about 0.74°/Ma, while the rate from 90.9 to 79.8 Ma (Phase II) is 0.19°/Ma. Based on paleolatitude change during Phase I, we infer that the Korean Peninsula (eastern part of the Sino-Korea Block) migrated southward about 300 km after the complete amalgamation of the Sino-Korea Block into the Eurasian continent resulting in N–S compression within the Korean peninsula and Manchuria. Large-scale strike-slip faults (e.g., Tan-Lu Fault, Okcheon Boundary Fault) were probably rejuvenated in the Sino-Korea Block during Phase I. 相似文献
9.
A virtual wave gauge (VWG) technique based on stereo imaging is developed to remotely measure water wave height, period, and direction. VWG minimizes computational costs by directly tracking the elevation of the water surface at selected points of interest using a Eulerian based dynamic searching algorithm. Results show that the VWG technique developed in this paper dramatically improves efficiency by two orders of magnitude compared to the traditional Lagrangian–Eulerian based point cloud method of stereo image processing. VWG is tested against traditional wave wire gauges to within 98% accuracy for significant wave height. Furthermore, the flexibility of the VWG is demonstrated in two field applications. First in an offshore breaking wave case, an array of VWGs is used to efficiently measure wave directionality. Second to investigate the reflection coefficient of a rock-mounted structure interacting with nearshore waves, linear and spatial VWG arrays are designed and implemented based on a priori information of the wave field from a preliminary VWG measurement. Overall, we demonstrate that the flexible and computational efficient VWG technique has the potential to make real-time remote stereo imaging wave measurements a reality. 相似文献
10.
This paper investigates the sensitivity of the numerical simulations of a near equatorial Typhoon Vamei (2001) to various
planetary boundary layer (PBL) parameterization schemes in the Pennsylvania State University (PSU)/National Centre for Atmospheric
Research (NCAR) non-hydrostatic mesoscale model (MM5). The numerical simulations are conducted on two domains at 45 and 15 km
grids nested in a one-way fashion. Four different PBL parameterization schemes including the Blackadar (BLK) scheme, the Burk–Thompson
(BURKT) scheme, the NCEP Eta model scheme and the NCEP medium range forecast (MRF) model scheme are investigated. Results
indicate that the intensity and propagation track of the simulated near equatorial typhoon system is not very sensitive to
the different PBL treatments. The simulated minimum central pressures and the maximum surface wind speeds differ by only 5–6 hPa
and 6–8 ms−1, respectively. Larger variations between the simulations occur during the weakening phase of the typhoon system. While all
schemes simulated the typhoon with reasonable accuracy, the ETA scheme produces the strongest storm intensity with the largest
heat exchanges over the marine environment and the highest warm moisture air content in the PBL around the core of the storm. 相似文献