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The Ministry of Finance on 25th June 2021 made some announcements to give relaxation in Income Tax compliances and also announced a tax exemption on COVID Financial Relief received on account of COVID-19.

2. Income-tax exemption to ex-gratia payment received by family members of a person, on death of the person on account of Covid-19 from:

Influence of reclaimed water on coastal groundwater quality is investigated.

Reclaimed water was comparable to that of groundwater mixed with urban wastewater.

Existing research on rock freeze-thaw mainly focuses on a single freeze-thaw process, while little attention is paid to the cumulative effect of cyclic freeze-thaw on rock mass joints. However, the accumulated freeze-thaw effects are precisely the leading cause of rock mass deterioration and damage in severe cold regions. This study aims to investigate the use of a novel laboratory testing method, i.e., membrane pressure sensors in the joint, to demonstrate the impact of cyclic frost-thaw on jointed rocks. With the sensors, the change of frost-heaving pressure in the joint under cyclic process is continuously monitored. The measurements indicate that under freeze-thaw cycles, the initiation of frost-heaving pressure is critical, which is followed by an explosion, stability, and ablation stages. In these stages, the maximum frost-heaving pressure is observed to emerge at the early stage of the freeze-thaw cycle. Based on the experimental observations, frost-heaving pressure evolution law and damage mechanism of jointed rock masses are analyzed. For example, the peak frost-heaving pressure increases exponentially with the decrease of temperature and decreases exponentially with the increase of freeze-thaw cycles. Also, the pressure has a positive linear relationship with the geometric size of the joint. In essence, the deterioration of freeze-thaw cycles on jointed rock masses is mainly due to crack propagation caused by the frost-heaving pressure.

One way to understand the frost heaving and its impact on the deterioration of rock mass is to carry out laboratory testing. For example, Davidson and Nye 17 used the photoelastic effect to measure the pressure caused by freezing expansion on transparent materials and found that the maximum ice pressure of a saturated crack with a width of 1 mm is 1.1 MPa. The frost-heaving pressure and the frost heave cracking in fractured rock masses were also measured by Huang et al. 18 through laboratory experiments, leading to the finding that the maximum frost-heaving pressure in a single fracture is 7.2 MPa. More quantification of the heaving pressures have been estimated by Winkler, 19 where the pressure caused by pore water freezing at -5 °C, -10 °C, and -20 °C may reach 61, 133, and 211 MPa, respectively, without considering the expansion of the pore volume. There are also a few other experimental research to measure the frost-heaving pressure in saturated rocks, e.g., Arosio et al. 20 studied the effects of porosity and lithology on the frost-heaving rock deformation and the crack propagation under freeze-thaw cycles.