共查询到20条相似文献,搜索用时 31 毫秒
1.
The tropospheric NO2 content over the Moscow region is analyzed on the basis of data of the satellite Ozone Monitoring Instrument (OMI) in the
period 2004–2009. The spatial distributions of NO2 are presented, and some of their features are interpreted. The characteristics of the seasonal and weekly cycles of NO2 are described, as are its interannual and long-term variations. The relationship between the variabilities of the NO2 content and the aerological parameters is investigated on different time scales. The mutual influence of regional pollution
and meteorological regimes is discussed. The seasonal and weekly NO2 cycles over Moscow are compared with those over the largest worldwide agglomerations. 相似文献
2.
Data on the NO2 content in the vertical column of the atmosphere obtained with the Ozone Monitoring Instrument (OMI) aboard the EOS Aura
satellite (United States) in the period from October 2004 to October 2007 are compared with the results of ground-based measurements
at the Zvenigorod Scientific Station (55.7° N, 36.8° E). The “unpolluted”; part of the total NO2 content in the atmospheric column, which mostly represents the stratosphere, and the NO2 contents in the vertical column of the troposphere, including the lower layer, which is subject to pollution, are included
in the comparison. The correlation coefficient between the results of ground-based and satellite measurements of the “unpolluted”
total NO2 content is ∼0.9. The content values measured with the OMI instrument are smaller than the results of ground-based measurements
(on average, by (0.30 ± 0.03) × 1015 cm−2 or by (11 ± 1)%). Therms discrepancy between the satellite and ground-based data is 0.6 × 1015 cm−2. The NO2 content in the vertical column of the troposphere from the results of satellite measurements is, on average, (1.4 ± 0.5)
× 1015 cm−2, (or about 35%) smaller than from the results of ground-based measurements, and the rms discrepancy between them is about
200%. The correlation coefficient between these data is ∼0.4. This considerable discrepancy is evidently caused by the strong
spatial (horizontal) inhomogeneity and the temporal variability of the NO2 field during episodes of pollution, which leads to different (and often uncorrelated) estimates of the NO2 content in the lower troposphere due to different spatial resolutions of ground-based and satellite measurements. 相似文献
3.
A. V. Poberovskii A. V. Shashkin D. V. Ionov Yu. M. Timofeev 《Izvestiya Atmospheric and Oceanic Physics》2007,43(4):505-513
An automatic spectral complex developed at the Institute of Physics, St. Petersburg State University, is described. This complex is used for regular ground-based spectroscopic measurements of the total NO2 content in the vertical column of the atmosphere during the twilight and daylight hours of the day near St. Petersburg (Petrodvorets). In 2004–2006, a number of ground-based twilight measurements of the total NO2 content were obtained near St. Petersburg, and variations in the NO2 content in the troposphere were estimated from the results of daytime ground-based measurements. An example of the spatial annual mean distribution of the NO2 content (central and northern Europe, northwestern Russia) based on the data of satellite measurements over the period 2003–2005 is presented. This example demonstrates the main sources of anthropogenic pollution. An increase in the mean annual contents of tropospheric NO2 near Moscow and St. Petersburg is preliminarily estimated for the entire period of satellite observations with the GOME instrument at about 30–40% over ten years. 相似文献
4.
The results of ground-based and satellite spectroscopic measurements of the tropospheric NO2 content near St. Petersburg in January–March 2006 are presented. It is shown that the increased concentrations of NO2 observed in St. Petersburg and its vicinities in this period were caused by NO2 accumulation due to unfavorable weather conditions, which is confirmed by an analysis of meteorological data and the results
of a numerical simulation of the dispersion of urban air pollutants. Data from satellite and ground-based measurements agree
with each other satisfactorily (a correlation coefficient of 0.5) and with model calculations of tropospheric NO2 conducted for the coordinates of a station of ground-based measurements (a correlation coefficient of 0.6). The HYSPLIT dispersion
model also made it possible to estimate the scale of the NO2 spatial-temporal variability in the near-surface layer in the vicinities of St. Petersburg. 相似文献
5.
M. V. Makarova A. V. Rakitin D. V. Ionov A. V. Poberovskii 《Izvestiya Atmospheric and Oceanic Physics》2011,47(4):468-479
The space-time variability of the fields of CO, NO2, and O3 concentrations and contents in the troposphere of northwestern Russia is analyzed on the basis of experimental data and the results of numerical modeling. The influence that the St. Petersburg emission has on the concentrations and contents of CO, NO2, and O3 in the troposphere is estimated for March 2006. A comparison of the measurements of the total CO content and the tropospheric NO2 content with the results of modeling showed a qualitative and, in come cases, quantitative agreement between the results of calculations and experimental data. When synoptic conditions are determined, the St. Petersburg train can be detected at a distance of more than 300 km, which can affect the atmospheric air quality in adjacent countries. 相似文献
6.
A. N. Gruzdev 《Izvestiya Atmospheric and Oceanic Physics》2013,49(2):137-147
Using the spectral method and the method of grouping by days of week, we analyzed the weekly cycles by standard air sounding data obtained at the Dolgoprudny station near Moscow and by the results of measurements of NO2 content in the stratosphere and the atmospheric boundary layer at the Zvenigorod Research Station of the Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences, in 1990–2010. We revealed weekly cycles of the NO2 content in the vertical column of the stratosphere, temperature, geopotential, meridional wind velocity in the troposphere and lower stratosphere, and the tropopause height in the warm half of the year (mid-April to mid-October). The weekly variations in temperature in the troposphere are positive in the first half of the week and negative in the second half, and the variations in temperature in the tropopause layer and in the lower stratosphere are opposite in sign to the tropospheric variations. The weekly cycle of the tropopause height is approximately in phase with the cycle of tropospheric temperature, and the weekly cycle of the NO2 content in the stratospheric column is opposite in phase to the cycle of the tropopause height. Weekly variations were also observed in the total ozone content over Moscow. This finding was confirmed by calculations based on regression relationships between the vertical distribution of ozone and tropopause height. Conceptual mechanisms of weekly cycles were proposed. 相似文献
7.
I. B. Konovalov 《Izvestiya Atmospheric and Oceanic Physics》2011,47(2):201-210
The influence that megalopolises have on the atmospheric composition on regional and global scales is the subject of intense
investigations; however, data on the emissions of pollutants used for such investigations are often insufficiently reliable.
In this work the possibilities for diagnosing long-term changes in nitrogen oxide emissions in megalopolises are investigated
based on a combined use of data from satellite measurements and modeling of the tropospheric nitrogen dioxide content. Primary
emphasis is placed on analyzing possible situations when emission changes are of a nonlinear character. The proposed methodology
includes an original method for the nonlinear approximation of changes in a physical quantity from a noised time series of
its measurements. Changes in NO
x
emissions are investigated in 12 megalopolises of Europe and the Middle East in the period from 1996 to 2008. Statistically
significant changes in NO
x
emissions are detected in five megalopolises (Baghdad, Madrid, Milan, Moscow, and Paris). By using three megalopolises (Madrid,
Milan, and Paris) as an example, it is shown that a nonlinear approximation of NO
x
emission changes agrees better with independent ground-based measurements than an analogous linear approximation. 相似文献
8.
Assessment of nitrogen loading from the Kiso-Sansen Rivers into Ise Bay using stable isotopes 总被引:1,自引:0,他引:1
Ryo Sugimoto Akihide Kasai Kouichi Fujita Kenichi Sakaguchi Tomomi Mizuno 《Journal of Oceanography》2011,67(2):231-240
Concentrations of particulate organic nitrogen (PN), dissolved inorganic nitrogen (DIN), and their nitrogen isotope ratios
(δ
15N) in the Kiso-Sansen Rivers were determined from monthly observations over the course of a year to assess variations in the
form and sources of riverine nitrogen discharged into Ise Bay. The δ
15N values of NO3
− observed in the Kiso-Sansen Rivers showed a logarithmic decreasing trend from 8 to 0‰, which varied with the river discharge,
indicating mixing between point sources with high δ
15N and non-point sources with low δ
15N. The influence of isotope fractionation of in situ biogeochemical processes (mainly DIN assimilation by phytoplankton) on
δ
15N of NO3
− was negligible, because sufficient concentrations of NH4
+ for phytoplankton demand would inhibit the assimilation of NO3
−. A simple relationship between river discharge and δ
15N of NO3
− showed that the fraction of total NO3
− flux arising from point sources increased from 4.0–6.3% (1.1–1.8 tN day−1) during higher discharge (>600 m3 s−1) to 30.2–48.3% (2.6–4.1 tN day−1) during lower discharge (<300 m3 s−1). Riverine NO3
− discharge from the Kiso-Sansen Rivers can explain 75% of the variations in surface NO3
− at the head of Ise Bay over the year. 相似文献
9.
Ryo Sugimoto Akihide Kasai Toshihiro Miyajima Kouichi Fujita 《Journal of Oceanography》2008,64(1):39-48
Temporal changes in nitrogen isotopic composition (δ15N) of the NO3
− pool in the water column below the pycnocline in Ise Bay, Japan were investigated to evaluate the effect of nitrification
on the change in the δ15N in the water column. The δ15N of NO3
− in the lower layers varied from −8.5‰ in May to +8.4‰ in July in response to the development of seasonal hypoxia and conversion
from NH4
+ to NO3
−. The significantly 15N-depleted NO3
− in May most likely arose from nitrification in the water column. The calculated apparent isotopic discrimination for water
column nitrification (ɛnit = δ15Nsubstrate − δ15Nproduct) was 24.5‰, which lies within the range of previous laboratory-based estimates. Though prominent deficits of NO3
− from hypoxic bottom waters due to denitrification were revealed in July, the isotopic discrimination of denitrification in
the sediments was low (ɛdenit = ∼1‰). δ15NNO3 in the hypoxic lower layer mainly reflects the isotopic effect of water column nitrification, given that water column nitrification
is not directly linked with sedimentary denitrification and the effect of sedimentary denitrification on the change in δ15NNO3 is relatively small. 相似文献
10.
Toshihiro Miyajima Yoshiyuki Tanaka Isao Koike Hiroya Yamano Hajime Kayanne 《Journal of Oceanography》2007,63(4):643-659
A Geographic Information System (GIS)-aided flow-tracking technique was adopted to investigate nutrient exchange rates between
specific benthic communities and overlying seawater in a fringing reef of Ishigaki Island, subtropical Northwestern Pacific.
Net exchange rates of NO3
−, NO2
−, NH4
+, PO4
3−, Total-N and Total-P were estimated from concentration changes along the drogue trajectories, each of which was tracked by
the Global Positioning System and plotted on a benthic map to determine the types of benthic habitat over which the drogue
had passed. The observed nutrient exchange rates were compared between 5 typical benthic zones (branched-coral (B) and Heliopora communities (H), seaweed-reefrock zone (W), bare sand area (S), and seagrass meadow (G)). The dependence of nutrient exchange
rates on nutrient concentrations, physical conditions and benthic characteristics was analyzed by multiple regression analysis
with the aid of GIS. The spatial correlation between nutrient exchange rates and benthic characteristics was confirmed, especially
for NO3
− and PO4
3−, which were usually absorbed in hydrographically upstream zones B and W and regenerated in downstream zones H and G. NO3
− uptake in zones B and W was concentration-dependent, and the uptake rate coefficient was estimated to be 0.58 and 0.67 m
h−1, respectively. Both nutrient uptake in zone W and regeneration in zone H were enhanced in summer. The net regeneration ratio
of NO3
−/PO4
3− in zone H in summer ranged 5.2 to 34 (mean, 17.4), which was somewhat higher than previously measured NO3
−/PO4
3− for sediment pore waters around this zone (1.1–8.5). Nutrient exchanges in zone S were relatively small, indicating semi-closed
nutrient cycling at the sediment-water interface of this zone. NH4
+ efflux from sediments was suggested in zone G. The data suggest that the spatial pattern of nutrient dynamics over the reef
flat community was constrained by zonation of benthic biota, and that abiotic factors such as nutrient concentrations and
flow rates, influenced nutrient exchange rates only in absorption-dominated communities such as zones B and W. 相似文献
11.
V. G. Bondur 《Izvestiya Atmospheric and Oceanic Physics》2011,47(9):1039-1048
We describe the specific features of the summer 2010 emergency conditions in the European part of the Russian Federation,
when an anomalous heat wave (the monthly mean temperatures in the summer months were 5–9°C higher than those for 2002–2009)
and prolonged blocking anticyclones led to large wildfires. We analyze their causes and consequences. The features of the
satellite system for operational fire monitoring (constructed at the Aerospace Scientific Center) and examples of its application
in summer 2010 are presented. On the basis of the results of processing of satellite images of low (250–1000 m), medium (∼30–50
m), and high (∼6 m) resolutions, we found that the total area covered by fire from March to November of 2010 amounted to approximately
10.9 million hectares for the entire territory of the country and and 2.2 million hectares for its European part. Daily histograms
of areas covered by fire in the summer months of 2010 were constructed. On the basis of these data and empirical models, we
estimate the daily emissions of carbon monoxide (CO) from wildfires in the summer months of 2010 for the European part of
Russia and Moscow oblast. On some days in August 2010, these emissions reached 15000–27000 t for the European part of Russia
and 3000–7500 t for Moscow oblast. On the basis of analysis of data from the AIRS spectrometer (Aqua satellite), we derived
the spatial distribution of CO concentrations at heights of 2 to 10 km above the territory of the Eastern and Central Europe.
Moscow was shown to have been most severely affected by smoke from wildfires occurring on August 6–9, 2010, when the concentrations
of harmful gases (CO2, CO, CH4, and O3) and aerosols in the air significantly exceeded both the daily and the one-hour maximum allowable concentrations. 相似文献
12.
Kuninao Tada Marut Suksomjit Kazuhiko Ichimi Yui Funaki Shigeru Montani Machiko Yamada Paul J. Harrison 《Journal of Oceanography》2009,65(6):885-891
The importance of the nitrogen source for phytoplankton growth in a highly eutrophic embayment, Dokai Bay, was investigated.
The DIN concentration often exceeded 100 μM of which 40–70% was NH4
+. During two incubation experiments, the natural assemblage of mainly diatoms took up NH4
+ instead of NO3
−. The growth of two Skeletonema species isolated in Dokai Bay were significantly faster on NH4
+ (1.86 and 1.27 div. d−1 respectively) than on NO3
− (1.55 and 1.04 div. d−1 respectively). Our results indicated that these diatoms could grow faster by using NH4
+ compared to NO3
− in this eutrophic bay. 相似文献
13.
Seasonal and interannual variations in physicochemical properties were investigated in the neritic area of Sagami Bay, Kanagawa,
Japan, from December 2000 to December 2005. Physicochemical properties (i.e. temperature, salinity, density, dissolved oxygen
and dissolved inorganic nutrient concentration) revealed clear seasonal variations, which were similar to each other during
all 5 years. Temperature, salinity and dissolved inorganic nutrients showed rapid, drastic variations within a few days and/or
weeks. These variations are related to sea levels, principally due to the shifting effects of the Kuroshio Current axis: they
were strongly affected by the Kuroshio Water and other waters, when sea level difference was greater than ca. 35 cm and lower
than ca. 15 cm, respectively. Temperature difference (DF
T
) increased with sea level difference, and the difference of salinity and dissolved inorganic nutrients (NH4
+-N, NO3
−+NO2
−-N, NH4
++NO3
−+NO2
−-N, PO4
3−-P and SiO2-Si) increased and decreased with DF
T
, respectively. All these correlations are significant. Total dissolved inorganic nitrogen (N), phosphate (P) and silicate
(Si) revealed seasonal variations in the ranges of 0.57–16.08, 0.0070–0.91 and 0.22–46.38 μM, respectively. From the regression equations between these elements allowed the following relation to be obtained; Si:N:P
= 14.8:13.4:1. Dissolved inorganic nutrients were characterized by Si and/or P deficiency, especially in the upper layer (0–20
m depth) during summer. Single and/or combined elements are discussed on the basis of potential and stoichiometric nutrient
limitations, which could restrict phytoplankton (diatom) growth as a limiting factor. 相似文献
14.
The results of spectroscopic measurements of tropospheric NO2 content performed on a closed route along the circular road around the city of St. Petersburg in 2012, 2014, and 2015 are presented. A procedure for determining the integral emission of NO x based on the data of measurements on the route enveloping the sources under study is described. An analysis of the experimental data together with the results of a numerical simulation of air pollutant dispersion (the HYSPLIT model) provided an estimate of the total volume of NO x emitted by all sources located inside the circular road. The average emission rate of NO x according to the sources of the megacity of St. Petersburg is 57000 t/yr, which correlates satisfactorily with the official data of a municipal inventory of the sources of air pollution (62000–63 000 t/yr). 相似文献
15.
海洋中的氮循环是海洋生物地球化学研究的热点领域之一,而硝化过程是氮循环的关键一环,准确获取硝化速率对于丰富海洋氮循环的认识至关重要。15N标记同位素技术是目前国际上最为广泛使用的硝化速率测定方法,该方法的核心在于准确测定15N加富样品产生的15NO2-和15NO3-的含量,但目前的方法普遍存在测试时间较长、测试成本较高、所需样品体积较大或者检测限较高等问题。研究以低成本的膜进样质谱作为15N加富样品测试设备,建立了基于镉柱与氨基磺酸双还原体系测定15N加富样品中15NO3-含量的方法。经条件优化实验确定的具体方法:采用1 mol/L HCl配制15 mmol/L的氨基磺酸(SA)作为反应试剂除去样品原有的NO2-,然后利用镉柱将15NO 相似文献
16.
Tomoyuki Shikata Sou Nagasoe Tadashi Matsubara Yasuhiro Yamasaki Yohei Shimasaki Yuji Oshima Takuji Uchida Ian R. Jenkinson Tsuneo Honjo 《Journal of Oceanography》2008,64(3):355-365
In the present study, we have investigated the conditions influencing encystment and excystment in the dinoflagellate Gyrodinium instriatum under laboratory conditions. We incubated G. instriatum in modified whole SWM-3 culture medium and in versions of modified SWM-3 from which NO3
−, PO4
3−, NO3
− + PO4
3−, or Si had been omitted and observed encystment. Percentage encystment was high in the media without N and without P, while
the percentage encystment in the medium lacking both N and P was highest. Moreover, to investigate N or P concentration which
induced the encystment, Gyrodinium instriatum was also incubated in media with different concentrations of inorganic N and P; the concentrations of NO2
− + NO3
− and PO4
3− were measured over time. The precursors of cysts appeared within 2 or 3 days of a decrease in NO2
− + NO3
− or PO4
3− concentration to values lower than 1 μM or 0.2 μM, respectively. When cysts produced in the laboratory were incubated, we observed excystment after 8–37 days, without a mandatory
period of darkness or low temperature. We incubated cysts collected from nature at different temperatures or in the dark or
light and observed excystments. Natural cysts excysted at temperatures from 10 to 30°C, in both light and dark, but excystment
was delayed at low temperatures. These studies indicate that G. instriatum encysts in low N or P concentration and excysts over a wide temperature range, regardless of light conditions, after short
dormancy periods. 相似文献
17.
Concentrations of nutrients (NO3, NO2, Si(OH)4, PO4 and dissolved inorganic carbon (DIC) were measured in a series of seawater samples collected over approximately 15 months
in 2005 and 2006 by an automatic water sampler (Remote Access Sampler, RAS) in the Northwestern North Pacific. Seasonal variability
and concentrations of NO3 + NO2 (NOx and Si(OH)4 were comparable to previous shipboard observations, although there were small errors associated with measurements of PO4 and DIC. Concentrations of these nutrients began to decrease in late April. After the end of June, NOx and Si(OH)4 decreased rapidly, with large fluctuations. After October, these nutrients increased again until late spring 2006. The ratio
of the decrease of Si(OH)4 to that of NOx suggests that numbers of biogenic opal-producing creatures, such as diatoms, increased after the end of June. This conclusion
was supported by a rapid increase in biogenic opal flux recorded in a sediment trap at 150 m. The relationship between NOx concentrations at the RAS depth of 35 m and NOx integrated over the upper 100 m was determined using previous shipboard hydrocast data. This relationship was used to estimate
integrated mixed layer NOx concentration from RAS data. Estimated new production based on seasonal drawdown of integrated NOx averaged approximately 156 mg-C m−2day−1 annually, which agrees with previous estimates. Thus, an automatic seawater sampler that documents annual maximum and minimum
nutrient concentrations and episodic events such as storms and spring blooms, which might be missed by an ordinary research
vessel, will contribute to time-series observations of nutrients and, by extension, biological pump activity. 相似文献
18.
Seasonal and latitudinal distributions of amplitudes of quasi-biennial variations in total NO2 content (NO2 TC), total ozone content (TOC), and stratospheric temperature are obtained. NO2 TC data from ground-based spectrometric measurements within the Network for the Detection of Atmospheric Composition Change (NDACC), TOC data from satellite measurements, and stratospheric temperature data from ERA-Interim reanalysis are used for the analysis. The differences in the NO2 TC diurnal cycles are identified between the westerly and easterly phases of the quasi-biennial oscillations (QBO) of equatorial stratospheric wind. The QBO effects in the NO2 TC, TOC, and stratospheric temperature in the Northern (NH) and Southern (SH) hemispheres are most significant in the winter–spring periods, with essential differences between the NH and SH. The NO2 TC in the Antarctic is less for the westerly phase of the QBO than that for the easterly phase, and the NO2 TC quasi-biennial variations in the SH mid-latitudes are opposite of the variations in the Antarctic. In the NH, the winter values of the NO2 TC are generally less during the westerly QBO phase than during the easterly phase, whereas in spring, on the contrary, the values for the westerly QBO phase exceed those for the easterly phase. Along with NO2, the features of the quasi-biennial variations of TOC and stratospheric temperature are discussed. Possible mechanisms of the quasi-biennial variations of the analyzed parameters are considered for the different latitudinal zones. 相似文献
19.
Katsuyuki Sasaki Tsuneo Ono Katsuhisa Tanaka Kiyoshi Kawasaki Hiroshi Saito 《Journal of Oceanography》1998,54(5):593-603
Partial pressure of CO2 in surface sea water (pCO2) was measured continuously off Sanriku in May, 1997 by a new pCO2 measurement system. We have examined the relation of pCO2 to physical factors such as temperature, salinity and density, chemical and biological factors such as nutrients and carbonate
system and chlorophylla. In the Kuroshio region pCO2 was not correlated to physical, chemical and biological factors in the range of 260 to 290 μatom. In transition water (Tr1)
between Kuroshio and the Oyashio second branch, pCO2 was weakly correlated to physical factors and strongly correlated to nutrients. In transition water (Tr2) between the Oyashio
first and second branches, pCO2 was highly correlated to temperature (SD: 10.9 μatom) and salinity (SD: 8.6 μatom) and also to nutrients. In transition water
(Tr1+Tr2), pCO2 was highly multivariately correlated to temperature (T), salinity (S), chlorophylla (CH) (or nitrate+nitrite (N)) as follows, pCO2(μatom)= 10.8×T(°C)+27.7×S+2.57CH(μg/1) −769, R2= 0.86, SD = 20.9, or pCO2(μatom)= 3.9×T(°C)+25.5×S+16.0NO3(μM) −686, R2= 0.99, SD = 6.4. Moreover, pCO2 was predicted by only two factors, one physical (S) and the other chemical/biological (N) as follows: pCO2 (μatom)=32.8×S+19.4N−908, R2=0.97, SD=8.4. The pH measured at 25°C was well correlated with normalized pCO2 at a fixed temperature. In the Oyashio region pCO2 was decreased to 160 μatom, probably because of spring bloom, but was not correlated linearly to chlorophylla. The results obtained showed the possibility of estimating pCO2 of the Oyashio and transition regions in May by satellite remote sensing of SST, but the problem of estimation of pCO2 in Kuroshio water remains to be solved. 相似文献
20.
A. V. Vivchar K. B. Moiseenko R. A. Shumskii A. I. Skorokhod 《Izvestiya Atmospheric and Oceanic Physics》2009,45(3):302-313
The task of identifying climatically significant regional anthropogenic emissions and estimating their contribution to the variability of nitrogen oxides observed at a monitoring station is considered on the basis of NO and NO2 surface concentrations measured at the Zotino background observation station (60°26′ N, 89°24′ E, Krasnoyarsk Territory). The approach used is based on an estimation of the conditional probability of polluted air arriving from individual regions by using the results of calculating backward Lagrangian trajectories in the lower troposphere. It is established that the contribution of air masses supplied from industrial regions in the south of the Krasnoyarsk Territory to episodes of high concentrations of nitrogen oxides (>0.7 ppb) is larger than the contribution from cities and towns located in the south of Western Siberia. The results indicate that anthropogenic sources of pollution substantially affect the balance of minor gases in the lower troposphere on a regional scale and that this factor must be taken into account when observational data from the Zotino background station are analyzed and interpreted. 相似文献