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1.
中国双相属(缓步动物门,高生熊虫科)三个新纪录种记述(英文) 总被引:3,自引:0,他引:3
本文记述了中国双相属(缓步动物门,高生熊虫科)三个新纪录种,它们是Diphascon modestum Binda.Pilato and Dastych,1984;Diphascon nobilei Binda,1969和Diphascon triodon Maucci,1996。D.modestum采自陕西省太白山2500m处(34°18’N,107°42’E),D.nobilei采自江西省铜鼓县900米处(28°31'N,114°26’E),D.triodon采自西藏自治区林芝地区3500m处(29°40'N,94°23’E)。所有标本保存于陕西师范大学生命科学学院。本文最后给出了中国双相属分种检索表。 相似文献
2.
Newly recorded species of the genus Isohypsibius (Tardigrada; Hypsibiidae) from China 总被引:9,自引:0,他引:9
This paper reports two newly recorded species, lsohypsibius lunulatus Iharos, 1966 and lsohypsibiusprosostomus Thulin, 1928, of the genus lsohypsibius (Tardigrada; Hypsibiidae) from China. The specimens of lsohysibius lunulatus were collected from Taibai Mt (34°18′N, 107°42′E) at 2,500 m a.s.1, and those oflsohypsibius prosostomus from Taibai Mt (34°10′N, 107°35′E) at 2,000 m above sea level. All specimens are deposited at the College of Life Sciences, Shaanxi Normal University, China. A key to the Chinese species of lsohypsibius was also given. 相似文献
3.
Using thermal dissipation and the ICT-2000TE equipment made in Australia, the sap flow of Castanopsis jianfengensis and various environmental factors were measured simultaneously in a mixed tropical montane rainforest at Jianfengling Nature
Forest Reserve (18°369′N, 108°52′E, 860 m elevation) during the dry and rainy seasons of 2002. The results show that sap flow
velocity of C. jianfengensis exhibited a monopeak pattern on clear days and a multi-peak pattern on cloudy or rainy days. Sap flow velocity had significant
positive correlations with solar radiation, air temperature, vapor pressure deficit and wind speed and a negative correlation
with air relative humidity. In the dry season, sap flow velocity had a significant positive correlation with soil temperature
and poor correlation with soil moisture; it was the opposite in the rainy season, indicating that precipitation clearly affected
sap flow. Linear regression models between sap flow and environmental factors were established and were significant at the
0.005 level of probability. The mean transpiration rates of C. jianfengensis were 103.5 and 41.3 kg/d in our single tree and 1.94 and 0.77 mm/d in stand level in the dry and rainy season, respectively.
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Translated from the Chinese Journal of Applied Ecology, 2007, 18(4): 742–748 [译自:应用生态学报] 相似文献
4.
Eight provenances of 19-year-oldPicea koraiensis Nakai from the provenance trials of Maoershan (45°20′N, 127°30′E), Liangshui (47°10′N, 128°53′E) and Jiagedaqi (50°24′N,
124°07′E) in Northeast China were investigated to analyze the genetic variation in growth characteristics (tree height and
diameter) and wood characteristics (tracheid length, tracheid diameter, tracheid wall thickness, annual ring width as well
as wood density). Great variation in height growth and breast height diameter growth was observed among the provenances, and
along with the increase of tree age, these provenances presented different geographic adaptability. The growth characteristics
ofPicea koraiensis stand at age of 10 in Maoershan and Liangshui provenance trials had a positive correlation with longitude, and with increase
of tree age to 15 and 19, the tree growth of the provenances displayed a significant positive correlation with latitude as
well as altitude. For wood characteristics, great variation was also found among the provenances. There exists a close relation
between growth characteristics and wood properties of the provenance. The height and breast height diameter growth of the
provenance had a positive correlation with tracheid diameter and annual ring width, and a negative correlation with tracheid
wall thickness and wood density. Genetic performance of the provenance in all above characteristics was also investigated
in order to provide more useful information for comprehensive selection of this species for pulpwood and plywood production.
Foundation item: The paper was supported by National Key Project of The State Forestry Administration. (96-011-01-06)
Biography: WANG Qiu-yu (1957-), female, professor in College of Life Sciences, Northeast Forestry University, Harbin 150040, P. R.
China.
Responsible editor: Song Funan 相似文献
5.
Reforestation is one of the most effective ways to reduce the impacts of desertification. Caragana microphylla Lam. and Pinus sylvestris var. mongolica Litrin have been widely used to stabilize shifting sands in the Horqin sandy land area since the 1980s. However, soil water
depletion has been of major concern in C. microphylla and P. ongolica plantations and in many places current soil moisture cannot meet the demand of growing plants. To determine the water budget
of C. microphylla and P. mongolica plantations, we studied the effect of plantations on soil moisture and assessed the evapotranspiration in plantations of
both species. Investigations were conducted at a fenced plot at Wulanaodu (42°29′N, 119°30′E, 479 m a. s. l), located at the
western edge of the Horqin Sandy Land area in Inner Mongolia, northern China. Five year old C. microphylla and seven year old P. mongolica plants were selected from the plantations and transplanted to iron boxes (400 cm×200 cm×120 cm) which can drain extra water.
Plant spacing of 1 m×1 m was applied to P. mongolica, and two plant spacings of 1 m×1 m and 1 m×2 m to C. microphylla. The transplanted plants grew for two years in the boxes. Soil moisture from soil surface to a depth 80 cm were measured
at 20 cm intervals in boxes every 10 d (2004) or 3 d (2005) during the growing season with a TDR water meter. The evapotranspiration
was estimated from a mathematical formula and the characteristics of soil water consumption and evapotranspiration of these
two plantations were analyzed. The soil water of P. mongolica was more than that of C. microphylla at the same 1 m×1m spacing. The soil water of C. microphylla with the 1 m×2 m spacing was more than that of the 1 m×1 m spacing. The evapotranspiration ranged from high to low as follows:
C. microphylla (1 m×1 m), C. microphylla (1 m×2 m) and P. mongolica (1 m×1 m) during the growing seasons. The evapotranspiration of individual plants ranging from high to low was C. microphylla (1 m×2 m), C. microphylla (1 m×1 m), and P. mongolica (1 m×1 m) during the growing season. C. microphylla grown for five year consumed more water than P. mongolica grown for seven years at the same spacing.
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Translated from Acta Ecological Sinica, 2008, 28(5): 1981–1990 [译自: 生态学报] 相似文献
6.
Miyake-Jima, a round island of about 8 km in diameter, is located about 200 km south of Tokyo, Japan (34°08′ N, 139°53′ E).
In July 2000, the central cone of this island collapsed and a new eruption started with the falling of volcanic ash and SO2 emission. In October 2001, we measured the distribution of bacteria, and Frankia, a symbiotic nitrogen-fixing actinomycete that forms root nodules, and ectomycorrhizal fungi associated with alder in newly
deposited ash and its underlying soil by cultivation of Alnus sieboldiana seedlings in these soils. There were fewer bacteria growing on the nutrient broth agar and fewer bacteria growing on 100-fold
diluted nutrient broth agar in newly deposited volcanic ash than there were growing in the buried old soil. In four out of
five sites, little or no nodulation was observed in newly deposited ash; abundant root nodules were formed in the underlying
soil. Ectomycorrhizae formed in the seedlings cultivated in the underlying soil. In May 2003, the distribution of Frankia and ectomycorrhizal fungi in soil at different depths (up to 160 cm) was also investigated. Frankia and ectomycorrhizal fungi were relatively abundant in surface soil layers. 相似文献
7.
Variations of fine root diameter with root order in Manchurian ash and Dahurian larch plantations 总被引:1,自引:0,他引:1
Xiangrong Wang Zhengquan Wang Youzhi Han Jiacun Gu Dali Guo Li Mei 《Frontiers of Forestry in China》2007,2(1):34-39
Fine root lifespan and turnover play an important role in carbon allocation and nutrient cycling in forest ecosystems. Fine
roots are typically defined as less than 1 or 2 mm in diameter. However, when categorizing roots by this diameter size, the
position of an individual root on the complex lateral branching pattern has often been ignored, and our knowledge about relationships
between branching order and root function thus remains limited. More recently, studies on root survivals found that longevity
was remarkably different in the same branching level due to diameter variations. The objectives of this study were: (1) To
examine variations of fine root diameter from the first-to fifth-orders in Fraxinus mandshurica Rupr and Larix gmelinii Rupr roots; and (2) To reveal how the season, soil nutrient, and water availability affect root diameter in different branch
order in two species. This study was conducted at Maoershan Forest Research Station (45°21′–45°25′N, 127°30′–127°34′E) owned
by Northeast Forestry University in Harbin, northeast China. Both F. mandshurica and L. gmelinii were planted in 1986. In each plantation, fine roots of two species by sampling up to five fine root branch orders three
times during the 2003 growing season from two soil depths (i.e., 0–10 and 10–20 cm) were obtained. The results showed that
average diameters of fine roots were significantly different among the five branch orders. The first-order had the thinner
roots and the fifth order had the thickest roots, the diameter increasing regularly with the ascending branch orders in both
species. If the diameter of fine roots was defined as being smaller than 0.5 mm, the first three orders of F. mandshurica roots and the first two orders of L. gmelinii roots would be included in the fine root population. The diameter ranges of the fine roots from first-order to fifth-order
were 0.15–0.58, 0.18–0.70, 0.26–1.05, 0.36–1.43, and 0.71–2.96 mm for F. mandshurica, and 0.17–0.76, 0.23–1.02, 0.26–1.10, 0.38–1.77, and 0.84–2.80 mm for L. gmelinii. The average coefficient of variation in first-order roots was less than 10%, second-and third-order was 10–20%, and fourth-and
fifth-order was 20–30%. Thus, variation in root diameter also increased with the ascending root order. These results suggest
that “fine roots”, which are traditionally defined as an arbitrary diameter class (i.e., <2 mm in diameter) may be too large
a size class when compared with the finest roots. The finest roots have much shorter lifespan than larger diameter roots;
however, the larger roots are still considered a component of the fine root system. Differences in the lifespan between root
diameter and root order affect estimates of root turnover. Therefore, based on this study, it has been concluded that both
diameter and branch order should be considered in the estimation of root lifespan and turnover.
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Translated from Acta Phytoecologica Sinica, 2005, 29(6): 871–877 [译自: 植物生态学报] 相似文献
8.
原产中国的榛属植物有8个种和2个变种,约占全世界种数的一半。榛子是传统的木本粮油树种,中国先民自古以来就采集野生榛子食用。中国榛属植物种质资源分布经纬跨度较大(24°31'~51°42'N、85°55'~132°12'E),从"东北—华北山区、秦岭和甘肃南部及河南—华中—云贵高原"呈斜带状,海拔从100~4 000 m都有分布,行政地域范围涉及25个省(自治区、直辖市)。通过地理分布生态适应性研究,建立了榛属植物分布种数与气候因子间的回归方程:Y=11.883-0.051X_1+0.131X_2-0.003X_4-0.004X_5-0.001X_6+0.051X_8。初步提出了榛属植物资源描述与评价体系,开展了榛坚果、花粉形态及雄花序等形态多样性研究,并且在分子水平上对榛属植物遗传多样性和系统进化进行了研究,明确了川榛应该作为一个独立的种,平榛与欧洲榛尽管地理位置较远,但是遗传距离较近,这既说明了平榛和欧洲榛杂交成功的原因,同时也为进一步研究榛树植物地理距离和遗传距离的不一致性提出了新的课题。 相似文献
9.
A study was conducted to determine the effects of elevated CO2 on soil N process at Changbai Mountain in Jilin Province, northeastern China (42°24′N, 128°06′E, and 738 m elevation). A
randomized complete block design of ambient and elevated CO2 was established in an open-top chamber facility in the spring of 1999. Changpai Scotch pine (Pinus sylvestris var. sylvestriformis seeds were sowed in May, 1999 and CO2 fumigation treatments began after seeds germination. In each year, the exposure started at the end of April and stopped at
the end of October. Soil samples were collected in June and August 2006 and in June 2007, and soil nitrifying, denitrifying
and N2-fixing enzyme activities were measured. Results show that soil nitrifying enzyme activities (NEA) in the 5–10 cm soil layer
were significantly increased at elevated CO2 by 30.3% in June 2006, by 30.9% in August 2006 and by 11.3% in June 2007. Soil denitrifying enzyme activities (DEA) were
significantly decreased by elevated CO2 treatment in June 2006 (P < 0.012) and August 2006 (P < 0.005) samplings in our study; no significant difference was detected in June 2007, and no significant changes in N2-fixing enzyme activity were found. This study suggests that elevated CO2 can alter soil nitrifying enzyme and denitrifying enzyme activities.
Foundation project: This research was supported by the National Natural Science Foundation of China (No. 90411020) and Major
State Basic Research Development Program of China (973 Program) (2002CB412502). 相似文献
10.
The concentrations and seasonal dynamics of DOC in forest floors of monoculture plantations ofCastanopsis kawakamii and Chinese fir (Cunninghamia lanceolata) were assessed in Sanming, Fujian, China (26°11′30″N, 117°26′00″E). Forest floor samples were taken in January, April, July
and October in 2002 and divided into undecomposed material (horizon Oi), partially decomposed organic material (horizon Oe),
and fully decomposed organic material (horizon Oa). Upon collection, DOC concentrations of samples were analyzed by a High
Temperature TOC. The results showed that the annual average DOC concentration of Chinese fir (1341.7 mg·kg−1) in the forest floor was higher than that ofCastanopsis kawakamii (1178.9 mg·kg−1). Difference in DOC concentrations was observed among three horizons of the forest floor. DOC concentration of forest floor
in the two forests was the highest in horizon Oe. Seasonal trends of DOC concentrations in different horizons of forest floors
were similar and the maximal value occurred in autumn (or winter). The concentration and temporal change of DOC in studied
forests were probably related to the variation in moisture, temperature, biological activity and quantity of organic matter
in the forest floor.
Foundation item: This study was supported by the Teaching and Research Award program for MOE P.R.C. (TRAPOYT)
Biography: ZHANG Jiang-shan (1946-), male, Researcher in Fujian Normal University, Fuzhou 350007, P.R. China.
Responsible editor: Zhu Hong 相似文献
11.
Takanori Imai Sousuke Inoue Naomi Ohdaira Yasuyuki Matsushita Rie Suzuki Mariko Sakurai José Manoel Henriques de Jesus Salete Kiyoka Ozaki Zenesio Finger Kazuhiko Fukushima 《Journal of Wood Science》2008,54(6):470-475
Heartwood extracts from Amazonian trees cumaru-ferro (Dipteryx odorata), jatoba (Hymenaea courbaril), and guarita (Astronium lecointei) exhibit antioxidant activities comparable with that of α-tocopherol, a well-known antioxidant. This article reports the characterization of the antioxidant compounds in the extracts
of the three heartwoods. Silica gel column chromatography of the cumaru-ferro EtOAc extract yielded (−)-(3R)-7,2′,3′-trihydroxy-4′-methoxyisoflavan and (+)-(3R)-8,2′,3′-trihydroxy-7,4′-dimethoxyisoflavan. Silica gel column chromatography followed by preparative high-performance liquid
chromatography of the jatoba EtOAc extract yielded (−)-fisetinidol and (+)-trans-taxifolin. Chemical structures were assigned using electron-ionization mass spectrometry, 1H and 13C nuclear magnetic resonance (NMR) spectroscopy including nuclear Overhauser effect spectroscopy (NOESY), as well as optical
rotation and circular dichroism. Gas chromatography-mass spectrometry demonstrated that the isolated compounds were predominant
in the EtOAc extracts. In the guarita EtOAc extract, catechin and gallic acid were identified by comparing their retention
times and mass fragmentation patterns with those of authentic samples. Antioxidant activity determined by the 1,1-diphenyl-2-picrylhydrazyl
assay demonstrated that all these compounds had activities comparable with that of α-tocopherol.
Part of this report was presented at the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, August 2007 相似文献
12.
This paper reported two newly recorded species, Hypsibius convergens Urbanowicz, 1925 and Hypsibius hypostomus Bartoš, 1935, of the genus Hypsibius (Tardigrada; Hypsibiidae) from China. Both species were collected from Taibai Mt, Shaanxi Province. All specimens are deposited
at the College of Life Sciences, Shaanxi Normal University, China.
Foundation project: This study was supported by scientific research foundation project of Shaanxi Institute of Education (No.
07KJ37Q) 相似文献
13.
Gao Chang-qi Sun Shou-hui Ren Xiao-guang Niu Yan-zhang Song Li-wen Zhang Yun-sheng 《林业研究》2000,11(2):114-118
Ips subelongatus Motschulsky were raised indoors and in the field using fresh baits for study of biological and ecological characteristics
during 1992–1994. The life cycle of the pest in Lishu County, Jilin Province was described. The study results indicated that
temperature was a main factor affecting the development ofIps subelongatus. The initial temperature for development of egg, larva, pupa and adult was 6.1, 8.0, 10.3 and 9.8°C, respectively. To complete
one-generation needs, respectively, 48 d at temperature of 18°C, 39 d at 20°C and 33 d at 22°C. The pest has different number
of generations in different area as a result of temperature change. In Jilin Province, it generally has three generations,
except that some individuals have 2 generations. The nature enemies for this pest areThanasinus substriatus, Tomimicobia seitneri Ruschk,Coeliodes sp. etc.
Foundation item: This paper is part of key subject of the Ministry of Forestry (formerly)—The Systematic Control Technique ofIps subelongatus Motschulsky.
Biography: G{upao} Chang-qi (1952-), male, research fellow in Jilin Forestry Academy.
Responsibe editor: Chai Ruihai 相似文献
14.
MD. Atiar Rahman Takeshi Katayama Toshisada Suzuki Takashi Nakagawa 《Journal of Wood Science》2007,53(2):161-167
Steps leading to the biosynthesis of syringyl lignans and tetrahydronaphthalene and naphthalene lignans, especially the formation
of the C2–C7′ linkage, have not been elucidated. Lyoniresinol is a typical syringyl lignan, as well as a tetrahydronaphthalene
lignan found in Lyonia ovalifolia var. elliptica. To demonstrate the biosynthetic pathway for (+)-lyoniresinol, three putative biosynthetic intermediates of lyoniresinol,
syringaresinol, 5,5′-dimethoxylariciresinol, and 5,5′-dimethoxysecoisolariciresinol, were isolated from wood. The identity
of the putative intermediates was confirmed by spectroscopic analyses, as well as by comparison of spectral and chromatographic
data with those of authentic samples previously synthesized. The stereochemistry (enantiomeric composition and absolute configuration)
of the isolated lignans were determined as (±)-syringaresinol, (8S,8′S)-(−)-5,5′-dimethoxylariciresinol [46% enantiomeric excess (e.e.)], (8S,8′S)-(+)-5,5′-dimethoxysecoisolariciresinol (91% e.e.), and (8R,8′R)-(+)-lyoniresinol (42% e.e.). The absolute configurations of (+)-and (-)-5,5′-dimethoxylariciresinols, and (+)-and (-)-5,5′-dimethoxysecoisolariciresinols
were determined by their synthesis (catalytic reduction) from (8R,8′R)-(+)-and (8S,8′S)-(-)-syringaresinols and by subsequent chiral high-performance liquid chromatography analysis.
This report was presented at the 55th Annual Meeting of the Japan Wood Research Society, Kyoto, March 2005 相似文献
15.
Based on the main characteristies of growth,ohenology and resistance at both seed-ling stage (one year old) and sampling stage (seven years old) of Dahurian larch (Larix gmelinii(Rupr.)Rupr.) from seventeen provenances in China ranging from 47°10′ to 52°25′N and 119° 57′to 130°25′E,the rules and patterns of infraspecific geolgraphic variation have been studied by using variance analysis,corelation analysis,partial correlation analysis and regression analysis.The best provenance for local site and its neighborhood was selected according to the growth char-acteristies of seven years provenance test on Liangshui Experimental Forest Farm of NortheastForestry University. 相似文献
16.
This paper summarizes several studies on N recycling in a tropical silvopastoral system for assessing the ability of the system
to increase soil fertility and insure sustainability. We analyzed the N2 fixation pattern of the woody legume component (Gliricidia sepium), estimated the recycling rate of the fixed N in the soil, and measured N outputs in tree pruning and cut grass (Dichanthium aristatum). With this information, we estimated the N balance of the silvopastoral system at the plot scale. The studies were conducted
in an 11-year-old silvopastoral plot established by planting G. sepium cuttings at 0.3 m × 2 m spacing in natural grassland. The plot was managed as a cut-and-carry system where all the tree pruning
residues (every 2-4 months) and cut grass (every 40-50 days) were removed and animals were excluded. No N fertilizer was applied.
Dinitrogen fixation, as estimated by the 15N natural abundance method, ranged from 60-90% of the total N in aboveground tree biomass depending on season. On average,
76% of the N exports from the plot in tree pruning (194 kg [N] ha–1 yr–1) originated from N2 fixation. Grass production averaged 13 Mg ha–1 yr–1 and N export in cut grass was 195 kg [N] ha–1 yr–1. The total N fixed by G. sepium, as estimated from the tree and grass N exports and the increase in soil N content, was about 555 kg [N] ha–1 yr–1. Carbon sequestration averaged 1.9 Mg [C] ha–1 yr–1 and soil organic N in the 0-0.2 m layer increased at a rate of 166 kg [N] ha–1 yr–1, corresponding to 30% of N2 fixation by the tree. Nitrogen released in nodule turnover (10 kg [N] ha–1 yr–1) and litter decomposition (40 kg [N] ha–1 yr–1) contributed slightly to this increase, and most of the recycled N came from the turnover or the activity of other below-ground
tree biomass than nodules.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
17.
This study were carried out in the Experimental Forest (37° 48′ 10″ N, 127° 48′ 50″ E) of Gangwon Forest Development Institute,
Gamjeong-ri, Chuncheon, Gangwon-do Province, Korea from Dec. 1999 to Jul. 2002. Eight individuals (three males and five females)
of hazel grouse were captured and they were marked with a 14-g necklace-type transmitter. The surveying results showed that
females were more active than males throughout the year, but males were more mobile than females in spring. The degree of
movement for females and males was similar from summer to winter. The overlap degree of habitat was very large from spring
to autumn. Hazel grouse had greater shifts in area use in winter. They used similar area from spring to autumn, made a shift
in their habitat use in winter, and then shifted back to the previous habitat.
Foundation item: This paper was supported by the Agricultural R & D Promotion Center (No. 198046-3), Korea
Biography: Shin-Jae RHIM (1970-), male, Ph. Doctor in University Forests, Seoul National University, Suwon 441-744, Korea.
Responsible editor: Zhu Hong 相似文献
18.
Laurel (Laurus nobilis L.) seeds were collected from the west part of Turkey in the fall of 2002. Seeds with pericarp (+) or without pericarp (−)
were treated with 1000 mg/l, 2000 mg/l and 3000 mg/l GA3 concentrations, cold stratified at +4 ± 1°C for 25 and 50 days, punctured and seed coat removed to overcome and assess the
mechanism of laurel seed dormancy. A period of 50 days cold stratification and removing seed coat significantly increased
germination rate to 55% ± 1.91 (Mean ± SE) and 85% ± 3.00, respectively. None of the seeds with pericarp germinated regardless
of treatment they underwent. Results suggested that seed dormancy was mainly due to pericarp and perhaps inhibitors linked
to seed coat. 相似文献
19.
温度对大叶桃花心木(Swietenia macrophylla King)幼苗叶片的光合影响 总被引:2,自引:0,他引:2
本文研究了大叶桃花心木(Swietenia macrophylla King)一年生幼苗在经过夜温处理后的光响应曲线和在饱和光强下的CO2反应曲线.结果表明:在大气CO2浓度下,叶片的最佳光合作用温度在25-31℃之间,而在饱和CO2浓度下为31-35℃.在25℃以下光合速率开始降低,主要是由于羧化效率的降低,而当温度超过31℃时,光合速率下降,是因为羧化效率的降低和呼吸速率的增加.CO2浓度对光合的促进作用在低温下受到抑制,这意味着未来在CO2浓度增高的情况下,高浓度的CO2对热带常绿植物光合的促进在冬天低温情况下表现不十分明显.图4参23. 相似文献
20.
Delignified hinoki wood and cellulose as well as hinoki and lauan woods were carbonized at 590°C for 1 h. The dielectric properties
of these specimens were measured at 20°C in a frequency range of 20 Hz to 1 MHz. Inflection points in the dielectric constant
(ε′) versus the logarithm of frequency (log f) curves as well as in the logarithm of the electric conductivity (log σ) versus log f curves for all specimens prepared were recognized. Peaks in the dielectric loss and the imaginary part of the complex conductivity
versus the log f curves were detected in the frequency location corresponding to the inflection point in the ε′ and log σ versus log f curves. It was considered that this relaxation was responsible for the interfacial polarization observed in heterogeneous
materials because no permanent dipoles existed in the specimens carbonized above 500°C. The Cole–Cole circular arc law was
applied to account for this relaxation. Similar average relaxation times were obtained for all specimens. These results suggested
that the observed relaxation was ascribed to interfacial polarization at microscopic levels in the cell walls. 相似文献