---

During a comprehensive survey of the heterostigmatic mites associated with dung beetles in the hyrcanian forests, northern Iran, several colonies of the pygmephoroid mites including four species of the genus Spatulaphorus Rack, 1993, S. copridis Khaustov, 2007, S. gorganica Rahiminejad & Hajiqanbar, 2011, S. vladimiri Khaustov, 2005 and S. geotruporum Khaustov, 2005 phoretic on Geotrupes spiniger (Marsham, 1802) were found. This is the first record of S. geotruporum from Asia. Furthermore, this is the first record of phoresy of S. geotruporum on G. spiniger.

---

Following a short-term faunistic study on soil inhabiting heterostigmatic mites (Acari: Prostigmata: Heterostigmata), during spring-winter 2019, in Gorgan, Golestan Province, northern Iran, a total of six species from five genera of two families were identified. Among them Promicrodispus pumilis (Sevastianov, 1975) and Premicrodispus montanus Khaustov, 2006 are new records for mite fauna of Iran. The genus Promicrodispus Khaustov, 2017 is recorded for the first time for the mite fauna of Iran. Moreover, Pre. akermanae (Sevastianov & Al Douri, 1988), Paramicrodispus scarabidophilus Hajiqanbar & Rahiminejad, 2012, Pygmodispus (Allodispus) latisternus Paoli, 1911 and Scutacarus sphaeroideus Karafiati, 1959 were collected from soil in the sampling sites. The world distribution of the mites is reviewed.

---

Using CFD, the effect of burner angle on an aluminum rotary furnace performance is studied in the present study. Turbulent non-premixed combustion of natural gas and oxygen, radiation, furnace rotation, aluminum smelting and aluminum burn-off are considered in the proposed numerical model. According to the distinct phenomena occurring in an aluminum rotary furnace, the model divides the furnace into three zones: refractory lining, combustion zone and melt zone. Only heat can be transferred through interfaces of zones and mass transfer through them is not considered in such furnace modeling. Numerical simulations regarding burner angles form 0ᵒ to 15ᵒ revealed that the higher burner angles enhance the fuel and oxygen mixing and increases the resident time of combustion gases in the furnace atmosphere, which consequently improve the furnace performance and lower the aluminum melting rate. However, the simulation results also showed that burner angles more than 10ᵒ are not applicable due to refractory lining overheat. It was showed eventually that changing burner angle from 0ᵒ to 10ᵒ decreases furnace operation time by 35 minutes and increases furnace thermal efficiency from 65% to 74.7%.

---

Hybrid laser-arc welding is a new welding process which received particular attention in various industries because of its technological and economic advantages. This process combines a laser beam and an electric arc to incorporate the advantages of both laser and arc welding processes. The main goal of this paper is to evaluate the performance and ability of hybrid Nd:YAG laser-TIG welding compared to lone laser welding process for welding of aluminum foam sandwich (AFS) panels of AA6082. For this aim, a set of experiments for both laser and hybrid laser-TIG welding were done to investigate the effects of welding parameters including laser power, arc current and welding speed on weld dimensions. Then, appropriate welding parameters for the laser and hybrid laser-TIG welding of AFS panels were calculated by statistical analysis. The results show that laser power threshold for creating the keyhole was less in hybrid laser-TIG welding than lone laser welding. Moreover, increasing the laser power and decreasing the welding speed result in increasing both the weld depth and width. But, with increasing the arc current, the weld depth remains almost unchanged and only the weld width increases. Comparing the laser and hybrid laser-TIG results show that adding a 100 A arc to a 2000 W laser source can increase the welding speed from 2 to 3 m/min which prove the high ability and efficiency of hybrid laser-TIG welding process.

---

Darabgird is one of the ancient cities in Fars province. According to Iranian mythology, Darab Shah (Dariush, the Great) found the city in the Achaemenid period. But, due to the fact that 1.21% of total ceramics gathered from the city belongs to the Parthian era, we can accept that the city remained in use since Parthian period to the Islamic era. Data analysis shows that the city had a strong and intensive settlement during Sasanians, After the Arab conquest and the collapse of Pars province, some changes occurred in the function of urban spaces. Accordingly, the main settlement shifted to the north of the city. Apparently, the southern half of the city was abandoned in Islamic era. Finally, according to some other early Islamic cities, apparently in this period, the main settlement of the city shifted to outside of Sasanian city (in this case, north of the Sasanian fortifications) and we should survey this area to discover available evidences of this period. Unfortunately, this area is presently being used for agricultural purposes.

---