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In recent years, "Jin Gao Yu" that has been traded as a kind of jade has appeared in areas of the Luonan and Shangnan counties, Shangluo City, Shaanxi Province, attracting the attention of scholars and consumers for its delicate texture and warm color. In this study, infrared spectroscopy, Raman spectroscopy, X-ray diffraction analysis, and electron microprobe analysis were used to conduct a systematic gemmological test and an analysis of "Jin Gao Yu". The results show that "Jin Gao Yu" is a compact mineral aggregate dominated by dolomite, which contains quartz mineral inclusions. The color of "Jin Gao Yu" is grayish-white to earthy-yellow, the refractive index is about 1.54, and the relative density is about 2.86. Its crystal structure is basically the same as that of dolomite, both of which are trigonal systems with granular crystalloblastic textures. It has good crystallinity. The recrystallization phenomenon can be seen under a polarizing microscope. This study determined the species of "Jin Gao Yu", improved its gemological basic data, provided a theoretical basis for the identification of "Jin Gao Yu" in the future, and, also, provided a new direction for the use of dolomite. [ABSTRACT FROM AUTHOR]

Compared with the chemical vapor deposition method, the high-pressure and high-temperature (HPHT) method has some advantages, such as fast diamond crystal growth speed, mature technology and easy mass production. HPHT method synthetic diamond is widely used industrially, but gem-quality synthetic diamond from China has rarely been reported. In this work, the gem-quality diamond synthesized by State Key Laboratory of Superhard Materials, Jilin University, China (SKLSHM), using the cubic hinge press equipment by the HPHT method, was investigated by microscopy, field-emission scanning electron microscopy (FE-SEM) and Diamond View observations as well as infrared spectrometer, ultraviolet–visible spectrometer (UV spectrometer) and energy-dispersive x-ray fluorescence tests. FE-SEM observation showed that regular growth steps and obvious growth pits were common on the {100} surface, and they were consistent with the distribution of internal metal inclusions. In most cases, the {111} plane is significantly flatter than the {100} plane, which may be related to the surface atomic state. It also can be seen that the internal metal inclusions are easily aligned along the internal growth boundary,which may be due to the different growth rates of different crystal faces during diamond growth. The fluorescent image under Diamond View shows the special geometric growth zone structure. Cubes, octahedrons and rhombohedral dodecahedrons have different intensities of orange, yellow, blue and other uneven fluorescences, which can be used as the most important diagnostic evidence. [ABSTRACT FROM AUTHOR]

The black carbon (BC) mass concentration and the particle chemical compositions were continually measured at Changdao Island, which is a regional receptor site off the eastern coast of China. This island is in the transport passage of the continental outflow to the Pacific Ocean when the East Asia monsoon prevails in the winter and spring. The campaign period was for March and April 2011, which corresponded to heating and non-heating periods in northern China. The effect of BC emission source regions on BC measured at Changdao Island between the heating and non-heating periods was determined by integrating the total potential source contribution function (TPSCF) model with the new monthly emission inventory in 2010 and the fire counts retrieved from MODIS during the campaign. BC concentrations were determined to be highest for similar times of day for both the heating and non-heating periods: 4.27 μg m −3 at 8:00 AM and 3.06 μg m −3 at 9:00 AM, respectively. The probable source regions for BC were primarily located in Shandong and Jiangsu provinces (and in other neighboring provinces) for both periods. However, the source regions for the non-heating period extended more to the north and southwest than those of the heating period. TPSCF values were correlated with the emission rates from residential, industry, transportation, and power plants sources in the anthropogenic emission inventory. This correlation provides an indirect and qualitative process to verify the emission inventory. In the heating period, the predominant source was the residential source in the emission inventory, and this source had a significant effect on the BC concentration. The differing peak concentrations between the two periods may be observed because of the increased residential heating during the heating period, which suggested that the measures employed by the government and environmental managers to reduce the emissions of pollutants should be stricter in the identified source regions during the heating period. [ABSTRACT FROM AUTHOR]

Ambient aerosol samples were collected at an urban site and an upwind rural site of Beijing during the CAREBEIJING-2008 (Campaigns of Air quality REsearch in BEIJING and surrounding region) summer field campaign. Contributions of primary particles and secondary organic aerosols (SOA) were estimated by chemical mass balance (CMB) modeling and tracer-yield method. The apportioned primary and secondary sources explain 73.8% ± 9.7% and 79.6% ± 10.1% of the measured OC at the urban and rural sites, respectively. Secondary organic carbon (SOC) contributes to 32.5 ± 15.9% of the organic carbon (OC) at the urban site, with 17.4 ± 7.6% from toluene, 9.7 ± 5.4% from isoprene, 5.1 ± 2.0% from α-pinene, and 2.3 ± 1.7% from β-caryophyllene. At the rural site, the secondary sources are responsible for 38.4 ± 14.4% of the OC, with the contributions of 17.3 ± 6.9%, 13.9 ± 9.1%, 5.6 ± 1.9%, and 1.7 ± 1.0% from toluene, isoprene, α-pinene, and β-caryophyllene, respectively. Compared with other regions in the world, SOA in Beijing is less aged, but the concentrations are much higher; between the sites, SOA is more aged and affected by regional transport at the urban site. The high SOA loading in Beijing is probably attributed to the high regional SOC background (~2 μg m(-3)). The toluene SOC concentration is high and comparable at the two sites, implying that some anthropogenic components, at least toluene SOA, are widespread in Beijing and represents a major factor in affecting the regional air quality. The aerosol gaseous precursor concentrations and temperature correlate well with SOA, both affecting SOA formation. The significant SOA enhancement with increasing water uptake and acidification indicates that the aqueous-phase reactions are largely responsible SOA formation in Beijing.