No abstract available

[en] Highlights: • Chlorinated paraffins (CPs) were found ubiquitously in tree bark samples. • Wind patterns had little influence on CP profiles in the study region. • Theoretical air concentrations of CPs were used for source apportionment. • CP emissions from the production plant were influential at sites located 6 km away. • A combination of sources influenced the CP profiles at rural and urban-rural sites. Short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) were measured in tree bark samples. These samples were collected around a chemical industrial park containing several chlorinated paraffin (CP) production plants, in a nearby city (Zhengzhou), and along a transect between the industrial park and city. Theoretical air concentrations were back-calculated from concentrations in bark using a predictive equation for estimating equilibrium bark-air partition coefficients. We developed this equation from a series of previously published K_bark-air measurements. Comparison of the normalized concentration profiles along south to north transects showed that wind played only a minor role in CP concentrations and profiles in the region. Three distinct source profiles were found in the complex source region. A fingerprint analysis technique was used to quantify the contribution of each source to the CP burden at various locations along the transect. We found that CP profiles at sites up to 6 km from the industrial park were strongly influenced by CP plant emissions, whereas the sites located in the rural zone and rural-urban interface were influenced by a mixture of CP plant emissions and the neighboring city.

No abstract available

[en] Full text: In the article have been reviewed the measures on tubing string cleaning from asphalt-tar-paraffin sediments formed while oil boreholes exploitation. In order to solve these problems connected with cleaning from asphalt-tar-paraffin crystals and mechanical sediments has been developed a new mechanical device which has been tested in pipe cleaning workshop in OGPD named after N.Narimanov. Test results showed that besides cleaning the pipes from ATP crystals and other mechanic sedimentations the device also prevents roughness of the pipe from inner side and creates smoothness inside the pipe. As a result, sedimentation period of ATP crystals inside the pipe is reduced which leads to increase runtime period between overhaul periods for 1.5-2.0 times

[en] Full text: For transport regime designing, especially for oils with high viscosity and paraffin fraction, right selection of rheological equation to describe the flow of these oils is very important. The rheological-structural properties of these oils have been studied and the curve of displacement tension of oil depending on displacement velocity has been found. Analysis of results according to square Means method showed superiority of Gershell-Balkly three parametric models. Due to this, application of Gershell-Balkly model is usually preferred in engineering calculations. Using mode of Gershell-Balkly deduces the rated formula for define connection

[en] To improve processing of the natural and synthetic fiber threads on stocking-frames, they are treated by paraffin. Paraffin is applied in the amounts nearly equal to 0.1 -1.0 g for 10⁴ m of the thread's length. To determine amount of paraffin on thread and to determine uniformity if its application, a radiometric method has been developed. As a radioactive label, didocilephosphate of rare earths was used. This compound has good solubility in hydrocarbons and does not change physical properties of paraffin in the investigated field of its application as well as its concentration. It is possible to add to paraffin this radioactive label or a non-active label with subsequent its activation. Amount of paraffin, applied on a thread is determined by means of measurement of activity of thread samples of different length. Information about uniformity of paraffin application on thread have been obtained by means of autoradiography. It has been found that paraffin in mainly applied on the thread's bulges

[en] The background of high voltage multiplier hall is high, which effects our experiment. So it is critical to improve the shield of experiment hall. We measured and analyzed the background of experiment hall. By simulation, the article gives the scheme of improving wall and collimator. After adding paraffin beside the wall, we have done a simple validating experiment. The results on Iron target show that the improvement is very well. (authors)

[en] Highlights: • SCCPs are ubiquitous in various environmental matrices and biota. • SCCPs pose lethality, carcinogenicity, metabolism-disrupting effect et al. • Toxicity mechanism of SCCPs related to oxidative stress, endocrine disruption et al. • More attention needs to be paid to novel toxic targets of SCCPs. -- Abstract: Short-chain chlorinated paraffin (SCCP) pollution has become a global threat. Much attention has been paid to their environmental occurrence and toxicity. In this review, we summarized the wide distribution of SCCPs in various environmental matrices and biota, including human beings. Toxicokinetics and the toxicities of SCCPs, including lethality, hepatotoxicity, developmental toxicity, carcinogenicity, endocrine- and metabolism-disrupting effects, and immunomodulatory effects have been considered. The mechanisms of SCCP toxicity are mainly related to oxidative stress, metabolic disturbance, endocrine disruption and binding to biomacromolecules. In the future, further studies of SCCPs should focus on searching for their novel toxicity targets, and uncovering their toxic effects using transcriptomics, proteomics, metabolomics, and mutigenerational toxicity.

[en] Longitudinal and transverse shifts of an 8 cm parallel bounded beam of 34.2 GHz (8.77 mm) microwaves totally reflected from a paraffin prism have been investigated. The 45⁰ - 45⁰ - 90⁰ prism is 18 cm high by 25 cm on the sides and the index of refraction is 1.491. Longitudinal shifts as large as 3 cm have been measured in a single reflection near the critical angle for a beam linearly polarized in the plane of incidence. The shift for perpendicular polarization is approximately half this value. The results are in general agreement with the classical theory for the Goos-Haenchen effect. An incident beam polarized at 45⁰ to the incidence plane produces both parallel and perpendicular polarization shifts with values similar to the above. The shifts for both polarizations are reduced but are still distinctly separate if either a second prism or a metallic reflector is brought into the evanescent wave at millimeter distances from the interface. These results are in accordance with stationary phase calculations for two interfaces. It is found that a small (6 mm) transverse shift results if the prism is illuminated with circularly polarized microwaves

No abstract available